Updated on 2022/04/23

写真a

 
Akihiro Sasoh
 
Organization
Graduate School of Engineering Professor
Trustee / Vice President Director
Graduate School
Graduate School of Engineering
Undergraduate School
School of Engineering Mechanical and Aerospace Engineering
Title
Professor

Degree 1

  1. Doctor of Engineering ( 1989.3   The University of Tokyo ) 

Research Interests 1

  1. Space propulsion, Compressible fluid dynamics, High-enthalpy flow, Shock wave, Plasma, Laser, Supersonic flow

Research Areas 2

  1. Others / Others  / Fluidics

  2. Others / Others  / Aerospace Engineering

Current Research Project and SDGs 3

  1. Application of highly-repetitive pulse laser to aerospace engineering

  2. Non-chemical space propulsion

  3. Study on sonic boom

Research History 5

  1. Nagoya University   Director

    2019.4 - 2022.3

  2. Professor, Department of Aerospace Engineering, Nagoya University   Professor

    2006.4

      More details

    Country:Japan

  3. Professor, Institute of Fluid Science, Tohoku University   Professor

    2003.3 - 2006.3

      More details

    Country:Japan

  4. Associate Professor,Institute of Fluid Science, Tohoku University   Assistant Professor

    1991.7 - 2003.2

      More details

    Country:Japan

  5. Research associate, Department of Aeronautics, Nagoya University   Assistant

    1989.4 - 1991.6

      More details

    Country:Japan

Education 3

  1. The University of Tokyo   Graduate School, Division of Engineering   Aeronautics

    1986.4 - 1989.3

      More details

    Country: Japan

  2. The University of Tokyo   Graduate School, Division of Engineering   Aeronautics

    1984.4 - 1986.3

      More details

    Country: Japan

  3. The University of Tokyo   Faculty of Engineering   Department of Aeronautics

    1979.4 - 1984.3

      More details

    Country: Japan

Professional Memberships 9

  1. International Shock Wave Institute

    2013.5

  2. 日本衝撃波研究会

  3. レーザー学会

  4. 日本流体力学会

  5. 日本機械学会

  6. 日本航空宇宙学会   理事(編集担当)

  7. アメリカ航空宇宙学会

  8. 火薬学会

  9. 日本工学アカデミー

▼display all

Awards 4

  1. ISBEP (International Symposium on Beamed Energy Propulsion) Award

    2008.11   American Institute of Beamed Energy Propulsion  

  2. 日本航空宇宙学会論文賞

    1999.4   日本航空宇宙学会  

     More details

    Country:Japan

  3. 日本流体力学会竜門賞

    1998.2   日本流体力学会  

     More details

    Country:Japan

  4. トーキン科学技術振興財団 研究奨励賞

    1992.3   トーキン科学技術振興財団  

     More details

    Country:Japan

 

Papers 194

  1. Electrostatic-magnetic hybrid ion acceleration for high-thrust-density operation Reviewed International journal

    Ichihara D., Nakano R., Nakamura Y., Kinefuchi K., Sasoh A.

    JOURNAL OF APPLIED PHYSICS   Vol. 130 ( 22 )   2021.12

     More details

    Language:Japanese  

    DOI: 10.1063/5.0066083

    Web of Science

  2. Numerical Investigation of a Ballistic Range Free Flight Model Reviewed International journal

    Mahomed I, Roohani H., Skews B. W., Gledhill I. M. A., Yamashita Y., Fujiwara H., Suzuki T., Iwakaka A., Sasoh A.

    INTERNATIONAL JOURNAL OF AERONAUTICAL AND SPACE SCIENCES   Vol. 22 ( 6 ) page: 1293 - 1301   2021.12

     More details

  3. Energy conversion efficiency of electrical exploding foil accelerators Reviewed International journal

    D. Ichihara, G. Fukushima, D. Kuwabara, and A. Sasoh

    AIP Advances   Vol. 11 ( 9 )   2021.9

     More details

    Language:Japanese  

    DOI: 10.1063/5.0061699

    Web of Science

  4. Losing the shock wave front profile due to interaction with turbulence Reviewed International journal

    Fukushima Gaku, Wei Jiaxi, Ogawa Shingo, Hagiwara Jun, Nakamura Yusuke, Sasoh Akihiro

    FLUID DYNAMICS RESEARCH   Vol. 53 ( 2 )   2021.4

     More details

    Language:Japanese  

    DOI: 10.1088/1873-7005/abeda4

    Web of Science

  5. In-tube shock wave compression by piston effect of unsteady jet Reviewed

    Daisuke KUWABARA, Hirokatsu KAWASAKI, Akira IWAKAWA, Akihiro SASOH

    Mechanical Engineering Journa   Vol. 17 ( 3 )   2021.4

     More details

  6. Impacts of grid turbulence on the side projection of planar shock waves Reviewed International journal

    Fukushima G., Ogawa S., Wei J., Nakamura Y., Sasoh A.

    SHOCK WAVES   Vol. 31 ( 2 ) page: 101 - 115   2021.3

     More details

  7. Speckle beam-oriented schlieren technique Reviewed International journal

    Nakamura Yusuke, Suzuki Takumi, Kinefuchi Kiyoshi, Sasoh Akihiro

    EXPERIMENTS IN FLUIDS   Vol. 62 ( 1 )   2021.1

     More details

  8. Coupling analysis of unsteady aerodynamics and vehicle behavior with road input: Modeling and verification in road tests Reviewed International journal

    Maeda Kazuhiro, Tsubakino Daisuke, Hara Susumu, Sasoh Akihiro

    MECHANICAL ENGINEERING JOURNAL   Vol. 8 ( 4 )   2021

     More details

    Language:Japanese  

    DOI: 10.1299/mej.21-00095

    Web of Science

  9. Thrust Density Enhancement in an Electrostatic–Magnetic Hybrid Thruster Reviewed International journal

    Daisuke Ichihara, Koichiro Oka, Ayumi Higo,Yusuke Nakamura,Kiyoshi Kinefuchi,and Akihiro Sasoh

    JOURNAL OF PROPULSION AND POWER   Vol. 37 ( 6 ) page: 973 - 976   2021

     More details

    Language:Japanese  

    DOI: 10.2514/1.B38480

    Web of Science

  10. Investigations of unsteady aerodynamic effects generated by heave and pitch motion in different vehicle body shapes with model excitation tests Reviewed

      Vol. 17 ( 5 )   2020.9

     More details

  11. Influence of cellophane diaphragm rupture processes on the shock wave formation in a shock tube Reviewed International journal

    Gaku Fukushima, Takahiro Tamba, Akira Iwakawa, Akihiro Sasoh

    Shock Waves   Vol. 30 ( 5 ) page: 545 - 557   2020.7

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1007/s00193-020-00951-2

    Web of Science

  12. Application of laser energy deposition to improve performance for high speed intakes Reviewed

    A. Russell, M. Myokan, H. Bottinib, A. Sasohb, H. Zare-Behtasha and K. Kontis

    Propulsion and Power Research   Vol. 9 ( 1 ) page: 15 - 25   2020.3

     More details

  13. Repetitive Energy Deposition at a Supersonic Intake in Subcritical and Buzz Modes Reviewed International journal

    Manabu Myokan, Akiya Kubota, Akira Iwakawa and Akihiro Sasoh

    AIAA Journal   Vol. 58 ( 1 ) page: 107 - 117   2020.1

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.2514/1.J058519

    Web of Science

  14. High-Specific-Impulse Electrostatic Thruster with Argon Propellant Reviewed International journal

    Daisuke Ichihara, Toshihiro Matsuba, Akira Iwakawa, and Akihiro Sasoh

    Journal of Propulsion and Power   Vol. 36 ( 2 ) page: 256 - 263   2020

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.2514/1.B37675

    Web of Science

  15. Central and External Cathode Operations in a Diverging-Magnetic-Field Electrostatic Thruster Reviewed International journal

    D. Ichihara, Y. Nakagawa, A. Iwakawa and A. Sasoh

    Journal of Propulsion and Power   Vol. 36 ( 1 ) page: 68 - 77   2020

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.2514/1.B37636

    Web of Science

  16. Boundary Effect on the Laser-ablation Impulse Characteristics of a Flat-Head Cylinder Reviewed International journal

    Yusuke KATAGIRI, Daisuke ICHIHARA, Hisashi TSURUTA, and Akihiro SASOH

    Transactions of The Japan Society for Aeronautical and Space Sciences   Vol. 63 ( 3 ) page: 109 - 112   2020

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.2322/tjsass.63.109

    Web of Science

  17. Sunflower Effect: Enhancement of laser-pulse-induced impulse in the beam incident direction due to surface undulation Reviewed International journal

    Yusuke Katagiri and Akihiro Sasoh

    Physica Scripta   Vol. 94 ( 8 ) page: 085004   2019.8

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1088/1402-4896/ab1944

    Web of Science

  18. Experimental investigation of the interaction of a weak planar shock with grid turbulence in a counter-driver shock tube Reviewed International journal

    Takahiro Tamba, Gaku Fukushima, Masaya Kayumi, Akira Iwakawa and Akihiro Sasoh

    Physical Review Fluids   Vol. 4 ( 7 ) page: 073401   2019.7

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1103/PhysRevFluids.4.073401

    Web of Science

  19. Electrostatic-magnetic-hybrid thrust generation in central-cathode electrostatic thruster (CC-EST)

    Akihiro Sasoh , Hayato Kasuga, Yoshiya Nakagawa, Toshihiro Matsuba, Daisuke Ichihara, and Akira Iwakawa

    Acta Astronautica   Vol. 152   page: 137 - 145   2018.11

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.actaastro.2018.07.052

    Web of Science

  20. Amplification and attenuation of shock wave strength caused by homogeneous isotropic turbulence

    Tanaka K., Watanabe T., Nagata K., Sasoh A., Sakai Y., Hayase T.

    PHYSICS OF FLUIDS   Vol. 30 ( 3 )   2018.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.5019867

    Web of Science

  21. Rapid distortion theory analysis on the interaction between homogeneous turbulence and a planar shock wave Reviewed International journal

    T. Kitamura, K. Nagata, Y. Sakai, A. Sasoh and Y.Ito

    Journal of Fluid Mechanics   Vol. 802   page: 108 - 146   2016.9

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1017/jfm.2016.313

    Web of Science

  22. Electrostatic ion acceleration across a diverging magnetic field Reviewed International journal

    D. Ichihara, A. Uchigashima, A. Iwakawa, A. Sasoh

    Applied Physics Letters   Vol. 109 ( 5 ) page: 053901   2016.8

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.4960363

    Web of Science

  23. Moderation of near-field pressure over a supersonic flight model using laser-pulse energy deposition Reviewed International journal

    D. Furukawa,Y. Aoki, A. Iwakawa,A. Sasoh

    Physics of Fluids   Vol. 28 ( 5 ) page: 051701   2016.5

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.4950783

    Web of Science

  24. Anode Geometry Effects on Ion Beam Energy Performance in Helicon Electrostatic Thruster Reviewed International journal

    Akira Uchigashima,Teruaki Baba,Daisuke Ichihara,Akira Iwakawa,Akihiro Sasoh,Takuya Yamazaki,Shota Harada,Matsutaka Sasahara,Tomoji Iwasaki

    IEEE Transactions on Plasma Science   Vol. 44 ( 3 ) page: 306 - 313   2016.3

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1109/TPS.2016.2522079

    Web of Science

  25. Field experiment of blast wave pressure modulation past a turbulent flow Reviewed International journal

    Tamba Takahiro, Furukawa Daiki, Aoki Yuma, Kayumi Masaya, Iwakawa Akira, Sasoh Akihiro, Matsunaga Takehiro, Izumo Mitsuo, Sugiyama Yuta, Matsumura Tomoharu, Nakayama Yoshio

    SCIENCE AND TECHNOLOGY OF ENERGETIC MATERIALS   Vol. 77 ( 3-4 ) page: 91 - 97   2016

     More details

    Language:Japanese  

    Web of Science

  26. RAMAC25 Reviewed International journal

    Sasoh Akihiro

    HYPERVELOCITY LAUNCHERS   Vol. 10   page: 205 - 216   2016

     More details

  27. Laser Focusing Reviewed International journal

    Sasoh Akihiro

    EXPERIMENTAL METHODS OF SHOCK WAVE RESEARCH   Vol. 9   page: 99 - 108   2016

     More details

  28. Counter-Driver Shock Tube Reviewed International journal

    T.Tamba, T.M.Nguyen, K.Takeya, T.Harasaki, A.Iwakawa, A.Sasoh

    Shock Waves - An International Journal on Shock Waves   Vol. 25 ( 6 ) page: 667 - 674   2015.11

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1007/s00193-015-0594-z

    Web of Science

  29. In-Tube Catapult Launch from Rectangular-Bore Aeroballistic Range Reviewed International journal

    Akihiro Sasoh, Takahiro Imaizumi, Atsushi Toyoda, Takeshi Ooyama

    AIAA Journal   Vol. 53 ( 9 ) page: 2781 - U23   2015.9

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.2514/1.J053540

    Web of Science

  30. Frequency modulation in shock wave-boundary layer interaction by repetitive-pulse laser energy deposition Reviewed International journal

    T. Tamba, H. S. Pham, T. Shoda, A. Iwakawa and A. Sasoh

    Physics of Fluids   Vol. 27 ( 9 ) page: 10.1063/1.4931924   2015.9

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.4931924

    Web of Science

  31. Low-Boom Performance Demonstration of a Long, Staged Aftbody Reviewed International journal

    Toyoda Atsushi, Suzuki Kakuei, Imaizumi Takahiro, Sasoh Akihiro

    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES   Vol. 58 ( 5 ) page: 307 - 309   2015

     More details

    Language:Japanese  

    Web of Science

  32. Staged Aftbody for Alleviation of Tail Boom Reviewed International journal

    Atsushi Toyoda , Kakuei Suzuki , Takahiro Imaizumi , Akihiro Sasoh

    AIAA Journal   Vol. 52 ( 12 ) page: 2899 - +   2014.12

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.2514/1.J052518

    Web of Science

  33. Electrostatic Acceleration of Helicon Plasma using a Cusped Magnetic Field Reviewed International journal

    S.Harada,T.Baba,A.Uchigashima,S.Yokota,A.Iwakawa,A.Sasoh,T.Yamazaki,and H.Shimizu

    Applied Physics Letters   Vol. 105 ( 19 ) page: 194101(4pages)   2014.11

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.4900423

    Web of Science

  34. Statistical behavior of post-shock overpressure past grid turbulence Reviewed International journal

    Akihiro Sasoh,, Tatsuya Harasaki, Takuya Kitamura, Daisuke Takagi, Shigeyoshi Ito, Atsushi Matsuda, Kouji Nagata, Yasuhiko Sakai

    Shock Waves - An International Journal on Shock Waves   Vol. 24 ( 5 ) page: 489 - 500   2014.9

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1007/s00193-014-0507-6

    Web of Science

  35. Laser Energy Deposition Effectiveness on Shock-Wave Boundary-Layer Interactions over Cylinder-Flare Combinations Reviewed International journal

    T. Osuka, E. Erdem, N. Hasegawa, R. Majima, T. Tamba, S. Yokota, A. Sasoh, K. Kontis

    Physics of Fluids   Vol. 26 ( 9 ) page: 096103(17pages)   2014.9

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.4896288

    Web of Science

  36. Supersonic aerodynamic performance of truncated cones with repetitive laser-pulse energy depositions Reviewed International journal

    A. Sasoh, J.-H. Kim, K. Yamashita, T. Sakai

    Shock Waves - An International Journal on Shock Waves   Vol. 24 ( 1 ) page: 59 - 67   2014.1

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1007/s00193-013-0463-6

    Web of Science

  37. On Invariants in Grid Turbulence at Moderate Reynolds Numbers Reviewed International journal

    Takuya Kitamura,Kouji Nagata,Yasuhiko Sakai,Akihiro Sasoh,Osamu Terashima,Hiroki Saito,Tatsuya Harasaki

    Journal of Fluid Mechanics   Vol. 738   page: 378 - 406   2014.1

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1017/jfm.2013.595

    Web of Science

  38. Repetitive Pulse Performance of 1-μm Laser Ablation Propulsion onto Aluminum Reviewed International journal

    Hisashi Tsuruta , Bin Wang , Zhogyuan Wang , Shigeru Yokota, and Akihiro Sasoh

    Journal of Propulsion and Power   Vol. 30 ( 6 ) page: 1485 - 1489   2014

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.2514/1.B35288

    Web of Science

  39. Aerospace Application Reviewed International journal

    Sasoh Akihiro

    MICRO-NANO MECHATRONICS - NEW TRENDS IN MATERIAL, MEASUREMENT, CONTROL, MANUFACTURING AND THEIR APPLICATIONS IN BIOMEDICAL ENGINEERING     page: 271 - 285   2013

     More details

    Language:Japanese  

    Web of Science

  40. DRAG REDUCTION PERFORMANCE DUE TO REPETITIVE LASER PULSES ON THE BLUNT BODY Reviewed International journal

    Kim Jae-Hyung, Sasoh Akihiro

    PROCEEDINGS OF THE ASME/JSME/KSME JOINT FLUIDS ENGINEERING CONFERENCE 2011, VOL 1, PTS A-D     page: 3363 - 3368   2012

     More details

    Language:Japanese  

    Web of Science

  41. Laser Ablation Propulsion Performance of Surface-Modified Polyoxymethylene Reviewed International journal

    Sasoh Akihiro, Ogita Naoya, Shikida Mitsuhiro, Sinko John E.

    JOURNAL OF PROPULSION AND POWER   Vol. 28 ( 4 ) page: 840 - 847   2012

     More details

    Language:Japanese  

    DOI: 10.2514/1.B34372

    Web of Science

  42. Wave Drag Reduction with Acting Spike Induced by Laser-Pulse Energy Depositions Reviewed International journal

    Kim Jae-Hyung, Matsuda Atsushi, Sakai Takeharu, Sasoh Akihiro

    AIAA JOURNAL   Vol. 49 ( 9 ) page: 2076 - 2078   2011.9

     More details

    Language:Japanese  

    DOI: 10.2514/1.J051145

    Web of Science

  43. Interactions among baroclinically-generated vortex rings in building up an acting spike to a bow shock layer Reviewed International journal

    Kim Jae-Hyung, Matsuda Atsushi, Sasoh Akihiro

    PHYSICS OF FLUIDS   Vol. 23 ( 2 )   2011.2

     More details

    Language:Japanese  

    DOI: 10.1063/1.3534002

    Web of Science

  44. Effects of Propellant Surface Morphology on Laser Ablative Propulsion Performance Reviewed International journal

    Ogita Naoya, Shikida Mitsuhiro, Sasoh Akihiro

    BEAMED ENERGY PROPULSION: SEVENTH INTERNATIONAL SYMPOSIUM   Vol. 1402   2011

     More details

    Language:Japanese  

    DOI: 10.1063/1.3657030

    Web of Science

  45. Review on Japanese-German-US Cooperation on Laser-Ablation Propulsion Reviewed International journal

    Scharring Stefan, Sinko John E., Karg Stephanie, Eckel Hans-Albert, Roeser Hans-Peter, Sasoh Akihiro, Ogita Naoya, Umehara Noritsugu, Tsukiyama Yosuke

    BEAMED ENERGY PROPULSION: SEVENTH INTERNATIONAL SYMPOSIUM   Vol. 1402   2011

     More details

    Language:Japanese  

    DOI: 10.1063/1.3657015

    Web of Science

  46. In-Tube Rocket Propulsion Using Repetitive Laser Pulses Reviewed International journal

    Sasoh Akihiro

    JOURNAL OF THERMAL SCIENCE   Vol. 20 ( 3 ) page: 201 - 204   2011

     More details

    Language:Japanese  

    DOI: 10.1007/s11630-011-0458-5

    Web of Science

  47. Efficient Supersonic Drag Reduction using Repetitive Laser Pulses of up to 80 kHz Reviewed International journal

    Sasoh Akihiro, Kim Jae-Hyung, Yamashita Kiyokazu, Sakai Takeharu, Matsuda Atsushi

    BEAMED ENERGY PROPULSION: SEVENTH INTERNATIONAL SYMPOSIUM   Vol. 1402   2011

     More details

    Language:Japanese  

    DOI: 10.1063/1.3657050

    Web of Science

  48. Supersonic Drag Reduction with Repetitive Laser Pulses Through a Blunt Body Reviewed International journal

    Sasoh Akihiro, Sekiya Yohei, Sakai Takeharu, Kim Jae-Hyung, Matsuda Atsushi

    AIAA JOURNAL   Vol. 48 ( 12 ) page: 2811 - 2817   2010.12

     More details

    Language:Japanese  

    DOI: 10.2514/1.J050174

    Web of Science

  49. Modulations of a weak shock wave through a turbulent slit jet Reviewed International journal

    Kim Jae-Hyung, Sasoh Akihiro, Matsuda Atsushi

    SHOCK WAVES   Vol. 20 ( 4 ) page: 339 - 345   2010.8

     More details

    Language:Japanese  

    DOI: 10.1007/s00193-010-0265-z

    Web of Science

  50. A Review of Laser Ablation Propulsion Reviewed International journal

    Phipps Claude, Bohn Willy, Lippert Thomas, Sasoh Akihiro, Schall Wolfgang, Sinko John

    INTERNATIONAL SYMPOSIUM ON HIGH POWER LASER ABLATION 2010   Vol. 1278   page: 710 - +   2010

     More details

    Language:Japanese  

    Web of Science

  51. Usage Of Polyacetal Powders As Laser Ablation Propulsion Propellants Reviewed International journal

    Sasoh Akihiro, Ogita Naoya, Sinko John E.

    BEAMED ENERGY PROPULSION   Vol. 1230   page: 163 - +   2010

     More details

    Language:Japanese  

    Web of Science

  52. Update On CO2 Laser Ablation Of Polyoxymethylene At 101 kPa Reviewed International journal

    Sinko John E., Scharring Stefan, Ogita Naoya, Sasoh Akihiro, Eckel Hans-Albert, Roeser Hans-Peter

    INTERNATIONAL SYMPOSIUM ON HIGH POWER LASER ABLATION 2010   Vol. 1278   page: 548 - +   2010

     More details

    Language:Japanese  

    Web of Science

  53. Survey Of CO2 Laser Ablation Propulsion With Polyoxymethylene Propellant Reviewed International journal

    Sinko John E., Sasoh Akihiro

    BEAMED ENERGY PROPULSION   Vol. 1230   page: 231 - +   2010

     More details

    Language:Japanese  

    Web of Science

  54. Review: Laser-Ablation Propulsion Reviewed International journal

    Phipps Claude, Birkan Mitat, Bohn Willy, Eckel Hans-Albert, Horisawa Hideyuki, Lippert Thomas, Michaelis Max, Rezunkov Yuri, Sasoh Akihiro, Schall Wolfgang, Scharring Stefan, Sinko John

    JOURNAL OF PROPULSION AND POWER   Vol. 26 ( 4 ) page: 609 - 637   2010

     More details

    Language:Japanese  

    DOI: 10.2514/1.43733

    Web of Science

  55. Modeling CO2 Laser Ablative Impulse with Polymers Reviewed International journal

    Sinko John E., Phipps Claude R., Sasoh Akihiro

    INTERNATIONAL SYMPOSIUM ON HIGH POWER LASER ABLATION 2010   Vol. 1278   page: 699 - +   2010

     More details

    Language:Japanese  

    Web of Science

  56. Measurement Issues In Pulsed Laser Propulsion Reviewed International journal

    Sinko John E., Scharring Stefan, Eckel Hans-Albert, Roeser Hans-Peter, Sasoh Akihiro

    BEAMED ENERGY PROPULSION   Vol. 1230   page: 125 - +   2010

     More details

    Language:Japanese  

    Web of Science

  57. Laser Propulsion Standardization Issues Reviewed International journal

    Scharring Stefan, Eckel Hans-Albert, Roeser Hans-Peter, Sinko John E., Sasoh Akihiro

    INTERNATIONAL SYMPOSIUM ON HIGH POWER LASER ABLATION 2010   Vol. 1278   page: 780 - +   2010

     More details

    Language:Japanese  

    Web of Science

  58. Critical Fluences And Modeling Of CO2 Laser Ablation Of Polyoxymethylene From Vaporization To The Plasma Regime Reviewed International journal

    Sinko John E., Phipps Claude R., Tsukiyama Yosuke, Ogita Naoya, Sasoh Akihiro, Umehara Noritsugu, Gregory Don A.

    BEAMED ENERGY PROPULSION   Vol. 1230   page: 395 - +   2010

     More details

    Language:Japanese  

    Web of Science

  59. CO2 Laser Ablation Propulsion Area Scaling With Polyoxymethylene Propellant Reviewed International journal

    Sinko John E., Ichihashi Katsuhiro, Tsukiyama Yosuke, Ogita Naoya, Sakai Takeharu, Umehara Noritsugu, Sasoh Akihiro

    BEAMED ENERGY PROPULSION   Vol. 1230   page: 207 - +   2010

     More details

    Language:Japanese  

    Web of Science

  60. CO2 Laser Ablation Area Scaling And Redeposition On Flat Polyoxymethylene Targets Reviewed International journal

    Sinko John E., Scharring Stefan, Tsukiyama Yosuke, Ichihashi Katsuhiro, Ogita Naoya, Sasoh Akihiro, Umehara Noritsugu, Eckel Hans-Albert, Roeser Hans-Peter

    INTERNATIONAL SYMPOSIUM ON HIGH POWER LASER ABLATION 2010   Vol. 1278   page: 538 - +   2010

     More details

    Language:Japanese  

    Web of Science

  61. Richtmyer-Meshkov instability in laser plasma-shock wave interaction Reviewed International journal

    Sasoh A., Mori K., Ohtani T.

    SHOCK WAVES, VOL 2, PROCEEDINGS     page: 1199 - +   2009

     More details

    Language:Japanese  

    Web of Science

  62. Wall-Propelled, In-Tube Propulsion with Repetitive-Pulse Laser Ablation Reviewed International journal

    Sasoh Akihiro, Suzuki Shingo, Matsuda Atsushi

    JOURNAL OF PROPULSION AND POWER   Vol. 25 ( 2 ) page: 540 - 542   2009

     More details

    Language:Japanese  

    DOI: 10.2514/1.39999

    Web of Science

  63. Interaction between laser-induced plasma and shock wave over a blunt body in a supersonic flow Reviewed International journal

    Sakai T., Sekiya Y., Mori K., Sasoh A.

    PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING   Vol. 222 ( G5 ) page: 605 - 617   2008.8

     More details

    Language:Japanese  

    DOI: 10.1243/09544100JAERO294

    Web of Science

  64. Ablative impulse characteristics of polyacetal with repetitive CO2 laser pulses Reviewed International journal

    Suzuki Koji, Sawada Keisuke, Takaya Ryota, Sasoh Akihiro

    JOURNAL OF PROPULSION AND POWER   Vol. 24 ( 4 ) page: 834 - 841   2008

     More details

    Language:Japanese  

    DOI: 10.2514/1.32477

    Web of Science

  65. Wall-ablative, laser-driven in-tube accelerator Reviewed International journal

    Sasoh Akihiro, Suzukia Shingo, Matsuda Atsushi

    HIGH-POWER LASER ABLATION VII, PTS 1-2   Vol. 7005   2008

     More details

    Language:Japanese  

    DOI: 10.1117/12.786500

    Web of Science

  66. Time-resolved measurements of impulse generation in pulsed laser-ablative propulsion Reviewed International journal

    Anju Kohei, Sawada Keisuke, Sasoh Akihiro, Mori Koichi, Zaretsky Eugene

    JOURNAL OF PROPULSION AND POWER   Vol. 24 ( 2 ) page: 322 - 329   2008

     More details

    Language:Japanese  

    DOI: 10.2514/1.32017

    Web of Science

  67. Moderate-acceleration launch using repetitive-pulse laser ablation in a tube Reviewed International journal

    Sasoh Akihiro, Suzuki Shingo, Shimono Masaya, Sawada Keisuke

    JOURNAL OF PROPULSION AND POWER   Vol. 24 ( 5 ) page: 1144 - 1146   2008

     More details

    Language:Japanese  

    DOI: 10.2514/1.36168

    Web of Science

  68. Diagnostics and impulse performance of laser-ablative propulsion Reviewed International journal

    Sasoh Akihiro, Mori Koichi, Anju Kohei, Suzuki Koji, Shimono Masaya, Sawada Keisuke

    BEAMED ENERGY PROPULSION   Vol. 997   page: 232 - +   2008

     More details

    Language:Japanese  

    Web of Science

  69. Access to space without energy and propellant on board Reviewed International journal

    Sasoh Akihiro, Jeung In-Seuck, Choi Jeong-Yeol

    BEAMED ENERGY PROPULSION   Vol. 997   page: 37 - +   2008

     More details

    Language:Japanese  

    Web of Science

  70. Spatio-temporal filament behaviour in a dielectric barrier discharge plasma actuator Reviewed International journal

    Sasoh A., Kikuchi K., Sakai T.

    JOURNAL OF PHYSICS D-APPLIED PHYSICS   Vol. 40 ( 14 ) page: 4181 - 4184   2007.7

     More details

  71. Expansion tube operation with thin secondary diaphragm Reviewed International journal

    Furukawa Takeshi, Aochi Takanobu, Sasoh Akihiro

    AIAA JOURNAL   Vol. 45 ( 1 ) page: 214 - 217   2007.1

     More details

    Language:Japanese  

    DOI: 10.2514/1.23846

    Web of Science

  72. Pressure effect in a shock-wave-plasma interaction induced by a focused laser pulse Reviewed International journal

    Sasoh A., Ohtani T., Mori K.

    PHYSICAL REVIEW LETTERS   Vol. 97 ( 20 )   2006.11

     More details

  73. Impactless, in-tube sabot separation technique useful for modest-sized supersonic ballistic ranges Reviewed International journal

    Sasoh Akihiro, Oshiba Shin

    REVIEW OF SCIENTIFIC INSTRUMENTS   Vol. 77 ( 10 )   2006.10

     More details

    Language:Japanese  

    DOI: 10.1063/1.2360766

    Web of Science

  74. Shock-tube operation with laser-beam-induced diaphragm rupture Reviewed International journal

    Sasoh A, Takahashi T, Watanabe K, Torikai H, Yang QS

    AIAA JOURNAL   Vol. 44 ( 5 ) page: 1110 - 1112   2006.5

     More details

    Language:Japanese  

    Web of Science

  75. Acceleration history in laser-ablative impulse measured using Velocity Interferometer (VISAR) Reviewed International journal

    Mori Koichi, Anju Kohei, Sasoh Akihiro, Zaretsky Eugene

    HIGH-POWER LASER ABLATION VI, PTS 1 AND 2   Vol. 6261   2006

     More details

    Language:Japanese  

    DOI: 10.1117/12.669426

    Web of Science

  76. Ambient pressure dependence of laser-induced impulse onto polyacetal Reviewed International journal

    Watanabe Keiko, Mori Koichi, Sasoh Akihiro

    JOURNAL OF PROPULSION AND POWER   Vol. 22 ( 5 ) page: 1149 - 1151   2006

     More details

    Language:Japanese  

    DOI: 10.2514/1.22750

    Web of Science

  77. Speckle-beam oriented schlieren technique Reviewed

    Yusuke NAKAMURA, Takumi SUZUKI, Kiyoshi KINEFUCHI, Akihiro SASOH

    Experiments in Fluids   Vol. 62 ( 13 )   2021.1

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  78. Investigations of unsteady aerodynamic effects generated by heave and pitch motion in different vehicle body shapes with model excitation tests Reviewed

    Kazuhiro MAEDA, Daisuke TSUBAKINO, Susumu HARA, Akihiro SASOH

    Mechanical Engineering Journal   Vol. 17 ( 5 ) page: 20 - 276   2020.10

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1299/mej.20-00276

  79. In-tube shock wave compression by piston effect of unsteady jet Reviewed

    Daisuke KUWABARA, Hirokatsu KAWASAKI, Akira IWAKAWA, Akihiro SASOH, Tetsuya YAMASHITA and Koji TAGUCHI

    Mechanical Engineering Journal   Vol. 17 ( 3 )   2020.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1299/mej.19-00534

  80. Application of laser energy deposition to improve performance for high speed intakes Reviewed

    A. Russell, M. Myokan, H. Bottini, A. Sasoh, H. Zare-Behtasha and K. Kontis,

    Propulsion and Power Research   Vol. 19 ( 1 ) page: 15 - 25   2020.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.jppr.2019.11.002

  81. Similar Thrust Performance in Diverging-Magnetic-Field Electrostatic Thruster with Monoatomic Propellants Reviewed

    Daisuke Ichihara, and Akihiro Sasoh

    Journal of Propulsion and Power   Vol. 35 ( 1 ) page: 236 - 238   2019.1

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.2514/1.B37294

    Web of Science

  82. Effects of Repetitive Laser Energy Deposition on Supersonic Duct Flows

    Hoang Son Pham, Manabu Myokan, Takahiro Tamba, Akira Iwakawa, and Akihiro Sasoh

    AIAA JOURNAL   Vol. 56 ( 2 ) page: 542-553   2018

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.2514/1.J056190

  83. Operation Characteristics of Applied-Field Magnetoplasmadynamics Thruster Using Hollow Cathode

    Hayato KASUGA, Jeohun JEONG, Keisuke MIZUTANI, Akira IWAKAWA, Akihiro SASOH, Kohei KOJIMA, Tatsuya KIMURA, Yoshihiro KAWAMATA, and Masaaki YASUI

    Transactions of The Japan Society for Aeronautical and Space Sciences   Vol. 16 ( 1 ) page: 69-74   2018

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.2322/tastj.16.69

  84. Finite response time of shock wave modulation by turbulence

    Inokuma Kento, Watanabe Tomoaki, Nagata Koji, Sasoh Akihiro, Sakai Yasuhiko

    PHYSICS OF FLUIDS   Vol. 29 ( 5 )   2017.5

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.4982932

    Web of Science

  85. Effects of magnetic field profile near anode on ion acceleration characteristics of a diverging magnetic field electrostatic thruster

    D. Ichihara, A. Iwakawa, and A. Sasoh

    Journal of Applied Physics   Vol. 122 ( 4 ) page: 043302(10pages)   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.4995286

  86. Power matching between plasma generation and electrostatic acceleration in helicon electrostatic thruster

    Daisuke Ichihara, Yoshiya Nakagawa, Akira Uchigashima, Akira Iwakawa, Akihiro Sasoh, and Takuya Yamazaki

    Acta Astronautica   Vol. 139   page: 157–164   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.actaastro.2017.06.032

  87. Changes in divergence-free grid turbulence interacting with a weak spherical shock wave

    T. Kitamura, K. Nagata, Y. Sakai, A. Sasoh, and Y. Ito

    Physics of Fluids   Vol. 29   page: 065114(9pages)   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.4984835

  88. Mach-number Effect on Supersonic Drag Reduction using Repetitive Laser Energy Depositions over Blunt-Body

    Akira Iwakawa; Tatsuro Shoda; Ryosuke Majima; Son Hoang Pham; Akihiro Sasoh

    Transactions of the JSASS / Aerospace Technology Japan   Vol. 60 ( 5 ) page: 303–311   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  89. Impacts of laser energy deposition on flow instability over double-cone model

    Hoang Son Pham, Tatsuro Shoda, Takahiro Tamba, Akira Iwakawa and Akihiro Sasoh

    AIAA Journal   Vol. 55 ( 9 ) page: 2992-3000   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.2514/1.J055670

  90. Electrostatic/magnetic ion acceleration through a slowly diverging magnetic nozzle between a ring anode and an on-axis hollow cathode

    Akihiro Sasoh, Keisuke Mizutani, and Akira Iwakawa

    AIP Advances   Vol. 7   page: 065204(6pages)   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.4985380

  91. Ablation Spot Area and Impulse Characteristics of Polymers Induced by Burst Irradiation of 1μm Laser Pulses

    Hisashi Tsuruta, Oskar Dondelewski, Yusuke Katagiri, Bin Wang and Akihiro Sasoh

    Acta Astronautica   Vol. 136   page: 46-54   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.actaastro.2017.03.006

  92. Ten-Ampere-Level, Applied-Field-Dominant Operation in Magnetoplasmadynamic Thrusters

    Daisuke Ichihara, Tomoki Uno, Hisashi Kataoka, Jaehun Jeong, Akira Iwakawa, and Akihiro Sasoh

    Journal of Propulsion and Power   Vol. 33 ( 2 ) page: 360-369   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.2514/1.B36179

  93. Mach Number Effect on Supersonic Drag Reduction using Repetitive Laser Energy Depositions over a Blunt Body

    Iwakawa Akira, Shoda Tatsuro, Majima Ryosuke, Pham Son Hoang, Sasoh Akihiro

    TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES   Vol. 60 ( 5 ) page: 303-311   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    Web of Science

  94. Suppression of low-frequency shock oscillations over boundary layer by repetitive laser pulse energy deposition Reviewed

    Akira Iwakawa,Tatsuro Shoda,Hoang Son Pham,Takahiro Tamba,Akihiro Sasoh

    aerospace   Vol. 3(2)   page: 13   2016

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.3390/aerospace3020013

  95. Field experiment of blast wave pressure modulation past a turbulent flow Reviewed

    Takahiro Tamba, Daiki Furukawa, Yuma Aoki, Masaya Kayumi, Akira Iwakawa, Akihiro Sasoh, Takehiro Matsunaga, Mitsuo Izumo, Yuta Sugiyama, Tomoharu Matsumura, and Yoshio Nakayama

    Science and Technology of Energetic Materials   Vol. 77 ( 4 ) page: 91-97   2016

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  96. Suppression of low-frequency shock oscillations over boundary layer by repetitive laser pulse energy deposition

    Akira Iwakawa, Tatsuro Shoda, Hoang Son Pham, Takahiro Tamba, Akihiro Sasoh

    Aerospace   Vol. 13 ( 2 ) page: Article number 13   2016

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.3390/aerospace3020013

  97. Operation Characteristics of Steady-State, Applied Field, Rectangular Magnetoplasmadynamics (MPD) Thruster

    D.Ichihara, S.Harada, H.Kataoka, S.Yokota, A.Sasoh

    Journal of the Japan Society for Aeronautical and Space Sciences   Vol. 63 ( 2 ) page: 37-44   2015

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  98. Influence of Microscopic Crater Formation on Impulse Generated with Repetitive Pulsed Laser Ablation

    Hisashi Tsuruta, Bin Wang, Zhogyuan Wang, Akihiro Sasoh

    Aerospace Technology Japan   Vol. 13   page: 33-36   2015

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.2322/tastj.13.33

  99. Low-Boom Performance Demonstration of a Long, Staged Aftbody

    Atsushi Toyoda , Kakuei Suzuki , Takahiro Imaizumi , Akihiro Sasoh

    Trans.Japan Soc.Aero.Space Sci   Vol. 58 ( 5 ) page: 307-309   2015

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.2322/tastj.58.307

  100. Ring-Force Balance System for Small Wind Tunnels Reviewed

    Akira IWAKAWA,Takeshi OSUKA,Tatsuro SHODA,Akihiro SASOH,Hiromitsu KAWAZOE

    Transactions of The Japan Society for Aeronautical and Space Sciences, Aerospace Technology Japan   Vol. 13   page: 51-60   2015

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.2322/tastj.13.51

  101. Supersonic Drag Reduction over a Blunt-Body by Combination of Conical Spike and Energy Deposition

    A. Iwakawa, T. Osuka, R. Majima, T. Sakai, A. Sasoh

    Journal of the Japan Society for Aeronautical and Space Sciences   Vol. 62 ( 3 ) page: 99-106   2014

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.2322/jjsass.62.99

  102. Repetition Frequency Dependence of Wave Drag Reduction Induced by Laser-Pulse-Energy Depositions Reviewed

    Akira IWAKAWA, Takeharu SAKAI, Akihiro SASOH

    Aerospace Technology Japan   Vol. 11   page: 53-60   2013

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  103. Operation Characteristics of a Steady-State, Two-Dimensional MPD Thruster Using a Hollow Cathode

    Masaki Yonemoto, Akihiro Sasoh

    28 ISTS Special Issue of Transaction of JSASS   Vol. 10   page: Pb_7-Pb_12   2012

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  104. Laser Ablation Propulsion Performance of Surface-Modified Polyoxymethylene

    Akihiro Sasoh, Naoya Ogita, Mitsuhiro Shikida, John E. Sinko

    Journal of Propulsion and Power   Vol. 28 ( 4 ) page: 840-847   2012

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  105. 格子乱流のエネルギー減衰域における不変量について

    北村拓也,長田孝二,佐宗章弘,酒井康彦,寺島修,齋藤大輝, 原崎 辰耶

    日本機械学会論文集(B 編)   Vol. 78 ( 795 ) page: 1928-1941   2012

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

  106. Preheating Technique to Enhanse the Laser Ablation Impulse from Polymer Materials Reviewed

    Koichi Mori , Akihiro Sasoh

    International Journal of Aerospace Innovations   Vol. 3 ( 1 ) page: 51-57   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  107. Review of CO2 laser ablation propulsion with polyoxymethylene Reviewed

    John E. Sinko and Akihiro Sasoh

    International Journal of Aerospace Innovations   Vol. 3 ( 2 ) page: 93-129   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  108. Experimental Determination of the Impulse Coupling Coefficient - Standardization Issues Reviewed

    S. Scharring, J. E. Sinko, A. Sasoh, H.-A. Eckel and H.-P. Roser

    International Journal of Aerospace Innovations   Vol. 3 ( 1 ) page: 33-43   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  109. Impact Fracture Behavior of Ceramics and PE-Fiber-Reinforced Mortars

    Yasuhiro Tanabe, Masayoshi Yamada1, Akihiro Sasoh, Minoru Kunieda

    Key Engineering Materials   Vol. 484   page: 75-81   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  110. 胴体先端形状修正による翼胴型超音速複葉翼機のソニックブーム低減化

    大久保正幸, 豊田篤,山下博, 小川俊広,大林茂,清水克也,鈴木角栄,松田淳,佐宗章弘

    日本航空宇宙学会論文集   Vol. 59 ( 688 ) page: 119-125   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  111. In-Tube Rocket Propulsion Using Repetitive Laser Pulses

    Akihiro Sasoh

    Journal of Thermal Science   Vol. 20 ( 3 ) page: 1-4   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  112. Interactions among baroclimically-generated vortex rings in building up an acting spike to a bow shock layer

    Jae-Hyung Kim, Atsushi Matsuda, Akihiro Sasoh

    PHYSICS OF FLUIDS 23     page: 021703-1-4   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  113. Wave Drag Reduction with Acting Spike Induced by Laser-Pulse Energy Depositions Reviewed

    Jae-Hyung Kim, Atsushi Matsuda, Takeharu Sakai, Akihiro Sasoh

    AIAA Journal   Vol. 49 ( 9 ) page: 2706-2078   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  114. Experimental-Numerical Combination Diagnostics for Near-Field Flow over Supersonic Flight Model

    Atsushi Matsuda, Katsuya Shimizu, Kakuei Suzuki, Akihiro Sasoh, Keiichi Murakami, & Takashi Aoyama

    Transactions of JSASS Space Technology of Japan   Vol. 9   page: 37-41   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  115. Aluminum-extrusion, square-bore, aero-ballistic range for launching three-dimensional projectiles

    International Journal of Aerospace Innovations   Vol. 2 ( 3 ) page: 147-156   2010.9

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  116. The modulations of weak shock wave through turbulent slit jet

    Shock Waves   ( 20 ) page: 339-345   2010

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  117. Review: Laser Ablation Propulsion

    C. Phipps, M. Birkan, W. Bohn, H.-A. Eckel, H. Horisawa, T. Lippert, M. Michaelis, Y. Rezunkov, A. Sasoh, W. Schall, S. Scharring, and J. Sinko

    Journal of Propulsion and Power   Vol. 126 ( 4 ) page: 609-637   2010

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  118. Supersonic Drag Reduction with Repetitive Laser Pulses through a Blunt Body

    Akihiro Sasoh,Yohei Sekiya,Takeharu Sakai,Jae-Hyung Kim and Atsushi Matsuda

    AIAA Journal   Vol. 48 ( 12 ) page: 2811-2817   2010

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  119. *Wall-Propelled, In-Tube Propulsion with Repetitive-Pulse Laser Ablation

    Akihiro Sasoh, Shingo Suzuki and Atsushi Matsuda

    Journal of Propulsion and Power   Vol. 25 ( 2 ) page: 540-542   2009

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  120. Ablative Impulse Characteristics of Polyacetal with Repetitive CO2 Laser Pulses Reviewed

    Koji Suzuki, Keisuke Sawada Ryota Takaya, Akihiro Sasoh

    Journal of Propulsion and Power   Vol. 24 ( 4 ) page: 834-841   2008.7

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  121. Time-Resolved Measurements of Impulse Generation in Pulsed Laser-Ablative Propulsion Reviewed

    Kohei Anju, Keisuke Sawada, Akihiro Sasoh, Koichi Mori, Eugene Zaretsky,

    Journal of Propulsion and Power   Vol. 24 ( 2 ) page: 322-329   2008.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  122. Impulse Generation Mechanisms in Laser-Driven In-Tube Accelerator Reviewed

    Choi, J.-Y., Sasoh, A., Jeung, I.-S., Urabe, N. and Kleine, H.

    Transactions of The Japan Society for Aeronautical and Space Sciences   Vol. 51 ( 172 ) page: 71-77   2008

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  123. Moderate-Acceleration Launch Using Repetitive-Pulse Laser Ablation In Tube Reviewed

    Sasoh, A., Suzuki, S, Shimono, M. and Sawada, K.

    Journal of Propulsion and Power   Vol. 24   page: in press   2008

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  124. Interaction Between laser-Induced Plasma and Shock Wave Over a Blunt Body in a Supersonic Flow Reviewed

    Takeharu Sakai, Yohei Sekiya, Koichi Mori, and Akihiro Sasoh

    Journal of Aerospace Engineering   Vol. 222   page: 605-617   2008

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  125. レーザパルスにより誘起されるプラズマ-衝撃波干渉場 Reviewed

    森浩一,大谷俊朗,佐宗章弘

    日本機械学会論文集B   Vol. 73 ( 727 ) page: 670-675   2007.3

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

  126. Expansion Tube Operation with Thin Secondary Diaphragm Reviewed

    Takeshi Furukawa, Takanobu Aochi and Akihiro Sasoh

    AIAA J.   Vol. 45 ( 1 ) page: 214-217   2007.1

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  127. Spatio-temporal filament behavior in a dielectric barrier discharge plasma actuator Reviewed

    A. Sasoh, K. Kikuchi, and T. Sakai

    Journal of Physics D: Applied Physics   Vol. 40   page: 4181-4184   2007

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  128. *Pressure effect in plasma-shock wave interaction induced by laser pulse irradiation over a parabola Reviewed

    A. Sasoh, T. Ohtani and K. Mori

    Physical Review Letters   Vol. 97 ( 20 )   2006.11

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  129. Ambient Pressure Dependence of Laser-Induced Impulse onto Polyacetal Reviewed

    K. Watanabe, K. Mori and A. Sasoh

    J. Propulsion and Power   Vol. 22 ( 5 ) page: 1148-1151   2006.10

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  130. Impact-less, in-tube sabot separation useful for modest-sized supersonic ballistic ranges Reviewed

    Akihiro Sasoh and Shin Oshiba

    Review of Scientific Instruments   Vol. 77 ( 10 )   2006.10

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  131. Shock Tube Operation with Laser Beam Induced Diaphragm Rupture Reviewed

    A. Sasoh, T. Takahashi, K. Watanabe, H. Torikai, and Q-S. Yang

    AIAA Journal   Vol. 44 ( 5 ) page: 1110-1112   2006.5

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  132. Multiband Radiation Model for Simulation of Galileo Probe Entry Flowfield Reviewed

    S. MATUSYAMA, Y. SHIMOGONYA, N. OHNISHI, A. SASOH AND K. SAWADA

    Journal of Thermophysics and Heat Transfer   Vol. 20 ( 3 ) page: 611-614   2006.5

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  133. Suppression of discharge current oscillations in a Hall Thruster Reviewed

    N. Yamamoto, S. Yokota, K. Watanabe, A. Sasoh, K. Komurasaki and Y. Arakawa

    Trans. Japan Soc. Aero. Space Sci.   Vol. 48 ( 161 ) page: 169-174   2005

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  134. Numerical Simulation of Galileo Probe Entry Flowfield with Radiation and Ablation Reviewed

    S. Matsuyama, N. Ohnishi, A. Sasoh and K. Sawada,

    Journal of Thermophysics and Heat Transfer   Vol. 19 ( 1 ) page: 28-35   2005

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  135. Behavior of bubbles induced by the interaction of a laser pulse with a metal plate in water Reviewed

    A. Sasoh, K. Watanabe, Y. Sano and N. Mukai

    Applied Physics A   Vol. 80 ( 7 ) page: 1497-1500   2005

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  136. Blast wave characteristics under laser-driven in-tube accelerator operation conditions, Reviewed

    X. Yu, T. Ohtani, S. Kim, T. Ogawa, I-S. Jeung and A. Sasoh

    Science and Technology of Energetic Materials   Vol. 66 ( 2 ) page: 274-282   2005

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  137. Impulse Generation Using a 300-J-Class Laser with Confinement Geometries in Air Reviewed

    K. Watanabe and A. Sasoh

    Transaction of the Japan Society for Aeronautical and Space Sciences   Vol. 48 ( 159 ) page: 49-52   2005

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  138. Impulse dependence on propellant condition in laser-driven in-tube accelerator Reviewed

    A. Sasoh, N. Urabe, S. Kim and I.-S. Jeung

    Transaction of the Japan Society for Aeronautical and Space Sciences   Vol. 48 ( 160 ) page: 63-70   2005

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  139. レーザーピーニングで誘起される水中圧力波に対する金属板厚の影響 Reviewed

    渡辺圭子, 佐野雄二, 向井成彦, 鳥飼宏之, 佐宗章弘

      Vol. 5 ( 339 ) page: 161-166   2004

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

  140. Distributed-Memory Parallelization of Radiative Transfer Calculation in Hypersonic Flow Reviewed

    S. Matsuyama, N. Onishi, A. Sasoh and K. Sawada

    Parallel Computational Fluid Dynamics-New Frontiers and Multi-Disciplinary Applocations     page: 491-498   2003

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  141. Parallel Computation of Fully-Coupled Hypersonic Radiating Flowfield Using Multi-Band Model Reviewed

    S. Matsuyama, T. Sakai, A. Sasoh and K. Sawada

    Journal of Thermophysics and Heat Transfer   Vol. 17   page: 21-28   2003

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  142. Laser-Powerd Launch in Tube Reviewed

    A. Sasoh, M. Kister, N. Urabe and K. Takayama

    Transactions of the Japan Society for Aeronautics and Space Sciences   Vol. 46 ( 151 ) page: 52-54   2003

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  143. High Ram-Acceleration Using Open-Base Projectile Reviewed

    Y. Hamate, A. Sasoh and K. Takayama

    Journal of Propulsion and Power   Vol. 19   page: 190-195   2003

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  144. Impulse scaling in laser-driven in-tube accelerator Reviewed

    A. Sasoh, N. Urabe, S. Kim and I. -S. Jeung

    Applied Physics A   Vol. 77   page: 349-352   2003

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  145. Frequency Characteristics and Dynamical Behaviors of Self-Modulation In Vertical-Cavity Suface-Emitting Lasers Reviewed

    Q. Yang and A. Sasoh

    Optics Communications   Vol. 219   page: 307-315   2003

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  146. Numerical Investigation of High-Enthalpy Flows Generated by Expansion Tube Reviewed

    H. Otsu, T. Abe, Y. Ohnishi, A. Sasoh and K. Takayama

    AIAA Journal   Vol. 40   page: 2423-2430   2002

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  147. Impact of Unsteady Disturbance on Multi-Lane Traffic Flow Reviewed

    A. Sasoh

    Journal of the Physical Society of Japan   Vol. 71   page: 989-996   2002

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  148. Shock Wave Relation Containing Lane Change Source Term for Two-Lane Traffic Flow Reviewed

    A. Sasoh and T. Ohara

    Journal of the Physical Society of Japan   Vol. 71   page: 2075-2083   2002

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  149. Numerical and Experimental Investigation of Wave Dynamic Processes In High-Speed Train/Tunnels Reviewed

    Z. Jiang, K. Matsuoka, A. Sasoh and K. Takayama

    Acta Mechanica Sinica   Vol. 18   page: 209-226   2002

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  150. Impulse Enhancement of Laser Propulsion In Tube Reviewed

    A. Sasoh, J-Y. Choi, I-S. Jeung, N. Urabe, H. Kleine and K. Takayama

    Postepy Astronautyki   Vol. 27   page: 40-50   2001

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  151. Gun Interior Ballistic Performance with Ammonium Nitrate-Alcohol Propellants Reviewed

    A. Sasoh, T. Ogawa, K. Takayama, K. Ikuta, N. Nagayasu and S. Ohtsubo

    Journal of Propulsion and Power   Vol. 17   page: 120-124   2001

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  152. *Laser-driven in-tube accelerator Reviewed

    A. Sasoh

    Review of Scientific Instruments   Vol. 72   page: 1893-1898   2001

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  153. Plural voltage minima in an arc-heated channel flow Reviewed

    A. Sasoh

    Physics of Plasmas   Vol. 8   page: 1376-1383   2001

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  154. Small-Bore Ram Accelerator Operation Reviewed

    A. Sasoh, Y. Hamate and K. Takayama

    Journal of Propulsion and Power   Vol. 17   page: 622-628   2001

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  155. Effective Test Time Evaluation in High-Enthalpy Expansion Tube Reviewed

    A. Sasoh, Y. Ohnishi, D. Ramjaun, K. Takayama, H. Otsu and T. Abe

    AIAA Journal   Vol. 39   page: 2141-2147   2001

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  156. Nonlinear Stability of Optimal Velocity Traffic Flow Model to Unsteady Disturbance Reviewed

    A. Sasoh

    Journal of the Physical Society of Japan   Vol. 70   page: 3161-3166   2001

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  157. Laser-propelled ram accelerator Reviewed

    A. Sasoh

    Journal de Physique IV   Vol. 10 ( Pr11 ) page: 41-47   2000

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  158. Ionizing Nitrogen and Air Flows in a Superorbital Expansion Tube Reviewed

    T. J. McIntyre, A. I. Bishop, A. M. Thomas, A. Sasoh and H. Rubinsztein-Dunlop

    AIAA Journal   Vol. 38   page: 1685-1691   2000

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  159. Quantitative Effects of Projectile-Launch Tube Wall Friction on Ballistic Range Operation Reviewed

    A. Sasoh, S. Ohba and K. Takayama

    AIAA Journal   Vol. 38   page: 1709-1715   2000

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  160. Flow Establishment over Constrictor in Arcjet Operation Reviewed

    A. Sasoh

    Transactions of the Japan Society for Aeronautical and Space Sciences   Vol. 43   page: 23-30   2000

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  161. プリル硝安-アルコール混合物(ANA)の爆薬特性 Reviewed

    永易伸生, 河野雄次, 大坪信武, 生田一成, 佐宗章弘, 高山和喜

    火薬学会誌   Vol. 61   page: 114-119   2000

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

  162. Projectile acceleration in a single-stage gun at breech pressures below 50 MPa Reviewed

    A. Sasoh, S. Ohba and K. Takayama

    Shock Waves   Vol. 10   page: 235-240   2000

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  163. High-Enthalpy Expansion Tube Experiments with Gas Injection Reviewed

    A. Sasoh, R. G. Morgan, B. N. Littleton, T. J. McIntyre and A. I. Bishop

    AIAA Journal   Vol. 38   page: 2253-2259   2000

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  164. Ram accelerator operations at acceleration level up to 6 × 104 g Reviewed

    Y. Hamate, A. Sasoh and K. Takayama

    Journal de Physique IV   Vol. 10 ( Pr11 ) page: 3-9   2000

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  165. Investigation on utilization of liquid propellant in ballistic range experiments Reviewed

    A. Sasoh, S. Ohba, and K. Takayama

      Vol. 60   page: 205-211   1999

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  166. Diaphragm rupture. Impingement by a conically-nosed, ram-accelerator projectile Reviewed

    A. Sasoh, J. Maemura, S. Hirakata, K. Takayama, J. Falcovitz

    Shock Waves   Vol. 9   page: 19-30   1999

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  167. Use of ammonium nitrate-alcohol (ANA) for ballistic range propellant Reviewed

    A. Sasoh, T. Ogawa, K. Takayama

    Shock Waves   Vol. 9   page: 291-294   1999

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  168. Experiments on Attenuation of Weak Shock Waves in High-Speed Train Tunnels Reviewed

    A. Sasoh, K. Matsuoka, K. Takayama, S. Hirano, S. Ono, Y. Makino and K. Ootsuta

    JSME International Journal, Series B   Vol. 41   page: 814-821   1998

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  169. 衝撃波管実験に有用な任意同期マルチプレクサシステムの開発 Reviewed

    佐宗 章弘, 川端荘平, 門脇忠

    日本航空宇宙学会誌   Vol. 46   page: 311-313   1998

     More details

    Authorship:Lead author   Language:Japanese   Publishing type:Research paper (scientific journal)  

  170. Technology and Application Aspects of Applied Field Magnetoplasmadynamic Propulsion Invited Reviewed

    G. Krulle, M. Auweter-Kurtz and A. Sasoh

    Journal of Propulsion and Power   Vol. 14   page: 754- 763   1998

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  171. Numerical and Theoretical Studies on Detonation Initiation by A Supersonic Projectile Reviewed

    Y. Ju, G. Masuya and A. Sasoh

    Proceedings of 27th Symposium (International) on Combustion     page: 2225-2231   1998

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  172. Application of sound-absorbent plastic to weak-shock-wave attenuators Reviewed

    K. Ootsuta, K. Matsuoka, A. Sasoh and K. Takayama

    Review of Scientific Instruments   Vol. 69   page: 1724-1729   1998

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  173. 高速列車トンネル突入による圧縮波の衝撃波への遷移 Reviewed

    佐宗章弘, 松岡敬, 高山和喜

    日本機械学会論文集(B編)   Vol. 63   page: 3944-3951   1998

     More details

    Authorship:Lead author   Language:Japanese   Publishing type:Research paper (scientific journal)  

  174. ラム加速機の始動過程に関する実験研究 Reviewed

    佐宗章弘, 平形修二, 高山和喜

    日本航空宇宙学会誌   Vol. 46   page: 37-45   1998

     More details

    Authorship:Lead author   Language:Japanese   Publishing type:Research paper (scientific journal)  

  175. Attenuation of weak shock waves along pseudo-perforated walls Reviewed

    A. Sasoh, K. Matsuoka, K. Nakashio, E. Timofeev, K. Takayama, P. Voinovich, T. Saito, S. Hirano, S. Ono. Y. Makino

    Shock Waves   Vol. 8   page: 149-159   1998

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  176. Ram Accelerator Operation Analysis in Thermally Choked and Transdetonative Propulsive Modes Reviewed

    A. Sasoh and C. Knowlen

    Transactions of the Japan Society for Aeronautical and Space, Sciences   Vol. 40   page: 130-148   1997

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  177. Numerical Study of Detonation Initiation by a Supersonic Sphere Reviewed

    Y. JU and A. Sasoh

    Transactions of the Japan Society for Aeronautical and Space, Sciences   Vol. 40   page: 19-29   1997

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  178. Hollow Projectile Operation in the Ram Accelerator Reviewed

    A. Sasoh, A. J. Higgins, C. Knowlen, A. P. Bruckner

    Journal of Propulsion and Power   Vol. 12   page: 1183-1186   1996

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  179. The reflection of a shock wave over a cone Reviewed

    J. Yang, A. Sasoh, K. Takayama

    Shock Waves   Vol. 6   page: 267-273   1996

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  180. Thrust Formula for Applied-Field Maganetoplasmadynamic Thrusters Derived from Energy Conservation Equation Reviewed

    A. Sasoh and Y. Arakawa

    Journal of Propulsion and Power   Vol. 11   page: 351-356   1995

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  181. Experimental investigation on tunnel sonic boom Reviewed

    K. Takayama, A. Sasoh, O. Onodera, R. Kaneko, Y. Matsui

    Shock Waves   Vol. 5   page: 127-138   1995

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  182. *Characterization of disturbance propagation in weak shock-wave reflections Reviewed

    A. Sasoh and K. Takayama

    Journal of Fluid Mechanics   Vol. 277   page: 331-345   1994

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  183. Simple formulation of magnetoplasmadynamic acceleration Reviewed

    A. Sasoh

    Physics of Plasmas   Vol. 1   page: 464-469   1994

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  184. Generalized Hall Acceleration Reviewed

    A. Sasoh

    Journal of Propulsion and Power   Vol. 10   page: 251-254   1994

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  185. Scaled train tunnel simulator for weak shock wave generation experiment Reviewed

    A. Sasoh, O. Onodera and K. Takayama

    Review of Scientific Instruments,   Vol. 65   page: 3000-3004   1994

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  186. A high-resolution thrust stand for ground tests of low-thrust space propulsion devices Reviewed

    A. Sasoh and Y. Arakawa

    Review of Scientific Instruments   Vol. 64   page: 719-723   1993

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  187. Numerical Study on Atom-Molecule Radiation Flowfield around a Hypersonic Blunt Body Reviewed

    X.-Y. Chang, A. Sasoh and T. Fujiwara

    Transactions of the Japan Society for Aeronautics and Space Sciences   Vol. 35   page: 177-186   1993

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  188. バリスティック・レンジによる極超音速流実験(第1報)画像観測及びその処理方法 Reviewed

    張 新宇, 辺見 真, 佐宗 章弘, 藤原 俊隆

    日本航空宇宙学会誌   Vol. 41   page: 81-87   1993

     More details

    Language:Japanese   Publishing type:Research paper (scientific journal)  

  189. *Electromagnetic Effects in an Applied-Field Magnetoplasmadynamic Thruster Reviewed

    A. Sasoh and Y. Arakawa

    Journal of Propulsion and Power   Vol. 8   page: 98-102   1992

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  190. A weak shock wave reflection over wedges Reviewed

    A. Sasoh, K. Takayama and T. Saito

    Shock Waves   Vol. 2   page: 277-281   1992

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  191. 再突入時に形成される極超音速非平衡衝撃波層からの輻射熱伝達

    佐宗章弘, 張新宇, 村山俊之, 藤原俊隆

    日本航空宇宙学会誌   Vol. 39   page: 531-538   1991

     More details

    Authorship:Lead author   Language:Japanese   Publishing type:Research paper (scientific journal)  

  192. 荒川義博外部磁場のあるMPD推進機におけるホール加速 Reviewed

    佐宗章弘, アンダース E. ソレム

    日本航空宇宙学会誌   Vol. 37   page: 528-534   1989

     More details

    Authorship:Lead author   Language:Japanese   Publishing type:Research paper (scientific journal)  

  193. Steady-State Permanent Magnet Magnetoplasmadynamic Thruster Reviewed

    Y.Arakawa and A.Sasoh

    Journal of Propulsion and Power   Vol. 5   page: 301-304   1989

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  194. Steady-State MPD Arc Thruster with a Permanent Magnet Reviewed

    Y.Arakawa and A.Sasoh

    Journal of Propulsion and Power   Vol. 4   page: 287-289   1988

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

▼display all

Books 6

  1. Compressible Fluid Dynamics and Shock Waves

    Akihiro Sasoh( Role: Sole author)

    Springer  2020  ( ISBN:978-981-15-0503-4

     More details

    Language:English Book type:Textbook, survey, introduction

  2. 圧縮性流体力学・衝撃波

    佐宗章弘( Role: Sole author)

    コロナ社  2017.3 

     More details

    Language:Japanese Book type:Scholarly book

  3. ながれの事典

    神部勉(編)( Role: Joint author)

    丸善  2004 

     More details

    Language:Japanese

  4. 電気推進ロケット入門

    栗木恭一,荒川義博(編)( Role: Joint author)

    東京大学出版会  2003 

     More details

    Language:Japanese

  5. Ram Accelerators

    K. Takayama and A. Sasoh (eds)( Role: Joint author)

    Springer-Verlag, Heidelberg  1998 

     More details

    Language:English

  6. 衝撃波ハンドブック

    高山 和喜(編)( Role: Joint author)

    シュプリンガー・フェアラーク東京  1995 

     More details

    Language:Japanese

▼display all

Presentations 93

  1. Square-bore ballistic range for launching three-dimensional projectiles International conference

     More details

    Event date: 2009.7

    Language:English   Presentation type:Oral presentation (general)  

  2. Supersonic Drag Reduction with Repetitive Laser Pulses through a Blunt Body International conference

    40thAIAA Plasmadynamics and Laser Conference 

     More details

    Event date: 2009.6

    Language:English   Presentation type:Oral presentation (general)  

  3. Supersonic Drag Reduction with Repetitive Laser Pulses through a Blunt Body International conference

    47th AIAA Aerospace Sciences Meeting 

     More details

    Event date: 2009.1

    Language:English  

  4. Plasma Behavior Induced by Repetitive Laser Pulses

    39th Plasmadynamics and Lasers Conference, Seattle, Washington 

     More details

    Event date: 2008.7

    Language:English  

  5. Wall-Propelled, In-Tube Propulsion with Repetitive-Pulse Laser Ablation

    39th Plasmadynamics and Lasers Conference, Seattle, Washington 

     More details

    Event date: 2008.7

    Language:English  

  6. Unsteady Interaction of Blunt Bodies With Laser Induced Plasma in a Supersonic Flow

    39th Plasmadynamics and Lasers Conference, Seattle, Washington 

     More details

    Event date: 2008.7

    Language:English  

  7. Wall-ablative, laser-driven in-tube accelerator

    High-Power Laser Ablation Ⅶ, Taos, NM, USA 

     More details

    Event date: 2008.4

    Language:English  

  8. Moderate-Acceleration Launch Using Repetitive-Pulse Laser Ablation In Tube

    46th AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2008.1

    Language:English  

  9. Computational Simulation of Local Impulse Generation in Intense Laser-Solid Interaction

    46th AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2008.1

    Language:English  

  10. Optical Observation of Discharge Plasma Structure in DBD Plasma Actuator

    38th AIAA Plasmadynamics and Lasers ConferenceIn conjunction with the16th International Conference on MHD Energy Conversion , Miami, FL 

     More details

    Event date: 2007.6

    Language:English  

  11. Time-resolved and Integrated Laser Ablative Impulse Performance of Polyacetal

    38th AIAA Plasmadynamics and Lasers ConferenceIn conjunction with the16th International Conference on MHD Energy Conversion , Miami, FL 

     More details

    Event date: 2007.6

    Language:English  

  12. Laser-Ablative Propulsion Using Polyacetal at Low Ambient Pressures

    45th AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2007.1

    Language:English  

  13. Impulse Generation by Nd:YAG Laser Ablation of Aluminum

    45th AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2007.1

    Language:English  

  14. Experiments of Laser^Pulse-Induced Drag Modulation in Supersonic Flow International conference

    37th Plasmadynamics and Lasers Conference 

     More details

    Event date: 2006.6

    Language:English   Presentation type:Oral presentation (general)  

  15. Experiments of Laser-Pulse-Induced Drag Modulation in Supersonic Flow

    37th AIAA Plasmadynamics and Lasers Conference, San Francisco, California 

     More details

    Event date: 2006.6

    Language:English  

  16. Acceleration history in laser-ablative impulse measured using Velocity Interferometer (VISAR) International conference

    High-Power Laser Ablation Ⅵ, Taos, NM, U.S.A. 

     More details

    Event date: 2006.5

    Language:English   Presentation type:Oral presentation (invited, special)  

  17. Expansion Tube Operation with Thin Secondary Diaphragm International conference

    44th AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV, U.S.A. 

     More details

    Event date: 2006.1

    Language:English   Presentation type:Oral presentation (general)  

  18. Expansion Tube Operation with Thin Secondary Diaphragm

    44th AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2006.1

    Language:English  

  19. Toward the Optimal Operation of Laser-Driven In-Tube Accelerator

    44th AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2006.1

    Language:English  

  20. Numerical Analysis of Expanding Nonequilibrium Plasma in a Gas-Driven Laser Propulsion

    44th AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2006.1

    Language:English  

  21. Time-Resolved Force Measurement over Laser-Ablated Materials

    Fourth International Symposium on Beamed Energy Propulsion, Nara, Japan 

     More details

    Event date: 2005.11

    Language:English  

  22. Pulsed Laser Propulsion Performance of 11-cm Parabolic `Bell'Engines: CO2 TEA vs. EDL

    Fourth International Symposium on Beamed Energy Propulsion, Nara, Japan 

     More details

    Event date: 2005.11

    Language:English  

  23. Physical Processes of the Interaction Between Laser-Generated Plasma and Blast Wave Appearing in Laser-Driven In-Tube Accelerator Configuration

    Fourth International Symposium on Beamed Energy Propulsion, Nara, Japan 

     More details

    Event date: 2005.11

    Language:English  

  24. Impulse Characteristics of Laser-driven In-Tube Accelerator(LITA)

    Fourth International Symposium on Beamed Energy Propulsion, Nara, Japan 

     More details

    Event date: 2005.11

    Language:English  

  25. Blast Wave Formation by Laser-Sustained Nonequilibrium Plasma in the Laser-Driven In-tube Accelerator Operation

    Fourth International Symposium on Beamed Energy Propulsion, Nara, Japan 

     More details

    Event date: 2005.11

    Language:English  

  26. Numerical Simulation of Laser-Driven In-Tube Accelerator Operation

    Fourth International Symposium on Beamed Energy Propulsion, Nara, Japan 

     More details

    Event date: 2005.11

    Language:English  

  27. Secondary diaphragm rupture processes in expansiontube

    Proceedings of the 25th International Symposium on Shock Waves, Bangalore,India 

     More details

    Event date: 2005.7

    Language:English  

  28. Experimental study of the interaction between thelaser-generated plasma and a shock wave

    Proceedings of the 25th International Symposium on Shock Waves, Bangalore,India 

     More details

    Event date: 2005.7

    Language:English  

  29. Propulsive impulse generation using laser pulse - solid/gas interactions International conference

    International Workshop on Explosion, Shock Wave and Hypervelocity Phenomena 2005 (ESHP Workshop 2005) 

     More details

    Event date: 2005.7

    Language:English   Presentation type:Oral presentation (invited, special)  

    Country:Japan  

  30. Impulse Generation Scaling Laws in Laser-Driven In-Tube Accelerator

    36th AIAA Plasmadynamics and Lasers Conference, Toronto, Ontario 

     More details

    Event date: 2005.6

    Language:English  

  31. Time-Resolved Measurement of the Impulse Generation Processes in POM Laser-Ablation

    36th AIAA Plasmadynamics and Lasers Conference, Toronto, Ontario 

     More details

    Event date: 2005.6

    Language:English  

  32. Numerical Analysis of Laser-Driven In-Tube Accelerator Operation

    43rd AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2005.1

    Language:English  

  33. Calculation of Unsteady Flowfield in Expansion Tube Using Contact Surface Resolving Technique

    43rd AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2005.1

    Language:English  

  34. Fascinating Experimental Observations of Spatiotemporally Localized Flows Utilizing Pulsed Laser Energy International conference

    Colloquium at Dept. Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute 

     More details

    Event date: 2004.10

    Language:English   Presentation type:Oral presentation (invited, special)  

  35. Large impulse launch using 300-J CO2 TEA laser

    Third International Symposium on Beamed Energy Propulsion, Troy, New York 

     More details

    Event date: 2004.10

    Language:English  

  36. Experimental Investigation of Airbreathing Laser Propulsion Engines: CO2TEA vs. EDL

    Third International Symposium on Beamed Energy Propulsion, Troy, New York 

     More details

    Event date: 2004.10

    Language:English  

  37. Detailed Impulse Generation Mechanisms in the Laser-Driven In-Tube Accelerator

    Third International Symposium on Beamed Energy Propulsion, Troy, New York 

     More details

    Event date: 2004.10

    Language:English  

  38. Presence of shock wave like structures in pedestrian motion

    Proceedings of the 24th International Symposium on Shock Waves, Beijing, China 

     More details

    Event date: 2004.7

    Language:English  

  39. Active diaphragm rupture with laser beam irradiation

    Proceedings of the 24th International Symposium on Shock Waves, Beijing, China 

     More details

    Event date: 2004.7

    Language:English  

  40. Impulse characteristics of laser-induced blast wave in monoatomic gases

    Proceedings of the 24th International Symposium on Shock Waves, Beijing, China 

     More details

    Event date: 2004.7

    Language:English  

  41. Shock wave phenomena in underwater laser peening

    Proceedings of the 24th International Symposium on Shock Waves, Beijing, China 

     More details

    Event date: 2004.7

    Language:English  

  42. A Pulsed Plasma Thruster Using Water as the Propellant

    40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, Fort Lauderdale, Florida 

     More details

    Event date: 2004.7

    Language:English  

  43. Laser impulse generation required for space debris deorbiting(Invited Paper)

    High-Power Laser Ablation Ⅴ,Taos, New Mexico, USA 

     More details

    Event date: 2004.4

    Language:English  

  44. Laser-Induced Shock Impulse Generation and Its Aerospace Applications

    42nd AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2004.1

    Language:English  

  45. Laser Impulse Generation in Flight

    42nd AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2004.1

    Language:English  

  46. Active Shock-tube-diaphragm Rupture with Laser Beam Irradiation

    42nd AIAA Aerospace Sciences Meeting and Exhibit, Reno, Nevada 

     More details

    Event date: 2004.1

    Language:English  

  47. Useful In-space Impulse Generation Powered by Laser Energy

    Second International Symposium on Beamed Energy Propulsion, Sendai, Japan 

     More details

    Event date: 2003.10

    Language:English  

  48. In-Tube Laser Propulsion; Performance and Application Prospects

    Second International Symposium on Beamed Energy Propulsion, Sendai, Japan 

     More details

    Event date: 2003.10

    Language:English  

  49. Dependence of Initial Plasma Size on Laser-driven In-Tube Accelerator (LITA) Performance

    Second International Symposium on Beamed Energy Propulsion, Sendai, Japan 

     More details

    Event date: 2003.10

    Language:English  

  50. Trajectory-Based Heating Analysis of Galileo Probe Entry Flowfield with Radiation and Ablation

    36th AIAA Thermophysics Conference, Orlando, Florida 

     More details

    Event date: 2003.6

    Language:English  

  51. Advanced Laser-driven In-Tube Accelerators

    34th AIAA Plasmadynamics and Lasers Conference, Orlando, Florida 

     More details

    Event date: 2003.6

    Language:English  

  52. High-power/applied-field MPD research activities in Japan -- Past and future prospects International conference

    Technology and System Options Towards Megawatt Level Electric Propulsion, Gli Incontri di Lerici, Anno II-International Workshop 

     More details

    Event date: 2003.6

    Language:English   Presentation type:Oral presentation (invited, special)  

  53. レーザーとプラズマの相互作用による飛翔体の加速

    第15回「電磁力関連のダイナミックス」シンポジウム 

     More details

    Event date: 2003.5

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

    Country:Japan  

  54. 有限時間エネルギー開放を伴う流動とインパルス発生

    火薬学会 第62回通常総会並びに2003年度春季研究発表講演会 

     More details

    Event date: 2003.5

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

    Country:Japan  

  55. In-Tube Laser Propulsion Configurations

    First International Symposium on Beamed Energy Propulsion, Huntsville, Alabama 

     More details

    Event date: 2002.11

    Language:English  

  56. Vertical Launch Performance of Laser-driven In-Tube Accelerator

    First International Symposium on Beamed Energy Propulsion, Huntsville, Alabama 

     More details

    Event date: 2002.11

    Language:English  

  57. Numerical Analysis of Carbon Dioxide Flowfield in Expansion-Tube

    8th AIAA/ASME Joint Thermophysics and Heat Transfer Conference, St. Louis, Missouri 

     More details

    Event date: 2002.6

    Language:English  

  58. Assessment of the Thermochemical Model for a Super-orbital Reentry Flow

    8th AIAA/ASME Joint Thermophysics and Heat Transfer Conference, St. Louis, Missouri 

     More details

    Event date: 2002.6

    Language:English  

  59. Numerical Simulation of Galileo Probe Entry Flowfield with Radiation

    8th AIAA/ASME Joint Thermophysics and Heat Transfer Conference, St. Louis, Missouri 

     More details

    Event date: 2002.6

    Language:English  

  60. Laser-Driven In-Tube Accelerator Operation Using Monoatomic Gases

    33rd Plasmadynamics and Lasers Conference, Maui, Hawaii 

     More details

    Event date: 2002.5

    Language:English  

  61. Numerical Study of Laser-Induced Pulsed Airbreathing Propulsion

    33rd Plasmadynamics and Lasers Conference, Maui, Hawaii 

     More details

    Event date: 2002.5

    Language:English  

  62. Impulse enhancement by in-tude operation in laser propulsion (Invited Paper)

    High-Power Laser Ablation Ⅳ,Taos,USA 

     More details

    Event date: 2002.4

    Language:English  

  63. Numerical study of non-ideal diaphragm rupture in expansion tube

    AIAA Aerospace Sciences Meeting and Exhibit, 40th, Reno, NV 

     More details

    Event date: 2002.1

    Language:English  

  64. Open-base projectile performance in ram accelerator

    AIAA Aerospace Sciences Meeting and Exhibit, 40th, Reno, NV 

     More details

    Event date: 2002.1

    Language:English  

  65. Pressure and Thrust Generation Using Laser Beam Focusing Through Forward-Facing Reflector

    Proceedings of the 23rd International Symposium on Shock Waves, Fort Worth, Texas, USA 

     More details

    Event date: 2001.7

    Language:English  

  66. In-Situ Sampling of Gases and Debris from Volcanic Plumes

    Proceedings of the 23rd International Symposium on Shock Waves, Fort Worth, Texas, USA 

     More details

    Event date: 2001.7

    Language:English  

  67. Shock Wave Phenomena in Multilane Traffic Flows

    Proceedings of the 23rd International Symposium on Shock Waves, Fort Worth, Texas, USA 

     More details

    Event date: 2001.7

    Language:English  

  68. Magnetoplasmadynamic Experiments Using Expansion Tube

    Proceedings of the 23rd International Symposium on Shock Waves, Fort Worth, Texas, USA 

     More details

    Event date: 2001.7

    Language:English  

  69. LITA (Laser-driven In-Tube Accelerator) operation under elevated pressures

    AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 37th, Salt Lake City, UT 

     More details

    Event date: 2001.7

    Language:English  

  70. Numerical and experimental studies of laser-driven ram accelerator

    AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 37th, Salt Lake City, UT 

     More details

    Event date: 2001.7

    Language:English  

  71. Numerical simulation of transient flowfield in expansion-tube

    AIAA Thermophysics Conference, 35th, Anaheim, CA 

     More details

    Event date: 2001.6

    Language:English  

  72. Hypersonic flow generation and diagnostics in expansion tube

    AIAA/NAL-NASDA-ISAS International Space Planes and Hypersonic Systems and Technologies Conference, 10th, Kyoto, Japan 

     More details

    Event date: 2001.4

    Language:English  

  73. Laser-Driven In-Tube Accelerator: Reusable Space Launch System International conference

     More details

    Event date: 2001.4

    Language:English   Presentation type:Oral presentation (invited, special)  

  74. Parallel computation of fully-coupled hypersonic radiating flowfield using multi-band model

    Aerospace Sciences Meeting and Exhibit, 39th, Reno, NV 

     More details

    Event date: 2001.1

    Language:English  

  75. In-tube laser propulsion

    AIAA Plasmadynamics and Lasers Conference, 31st, Denver, CO 

     More details

    Event date: 2000.7

    Language:English  

  76. RAMAC25 multi-stage operation

    AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 36th, Huntsville, AL 

     More details

    Event date: 2000.7

    Language:English  

  77. Ram Accelerator Research Activities at Shock Wave Research Center International conference

    Fourth International Workshop on Ram Accelerators 

     More details

    Event date: 1999.9

    Language:English   Presentation type:Oral presentation (invited, special)  

  78. Simulation of ablative mixing layers in superorbital flows

    Proceedings of the 22nd International Symposium on Shock Waves 

     More details

    Event date: 1999.7

    Language:English  

  79. Soft launch using single-stage chemical gun

    Proceedings of the 22nd International Symposium on Shock Waves 

     More details

    Event date: 1999.7

    Language:English  

  80. High acceleration operation in a small-bore ram accelerator

    Proceedings of the 22nd International Symposium on Shock Waves 

     More details

    Event date: 1999.7

    Language:English  

  81. High acceleration ram accelerator operation

    AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 35th, Los Angeles, CA 

     More details

    Event date: 1999.6

    Language:English  

  82. Ballistic range performance of ammonium nitrate-alcohol (ANA) propellant

    AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 35th, Los Angeles, CA 

     More details

    Event date: 1999.6

    Language:English  

  83. Significance of unsteadiness in operation of the small bore ram accelerator

    AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 34th, Cleveland, OH 

     More details

    Event date: 1998.7

    Language:English  

  84. Ionization measurements in a super-orbital expansion tube

    Advanced Measurement and Ground Testing Technology Conference, 20th, Albuquerque, NM, 

     More details

    Event date: 1998.6

    Language:English  

  85. Experimental studies of 25-mm-bore ram accelerator at the Shock Wave Research Center

    AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 33rd, Seattle, WA 

     More details

    Event date: 1997.7

    Language:English  

  86. Benchmark test of reflection of weak shock waves from shallow wedges

    Proceedings of the 21st International symposium on Shock Waves 

     More details

    Event date: 1997.7

    Language:English  

  87. Attenuation of weak shock waves along pseudo-perforated walls

    Proceedings of the 21st International symposium on Shock Waves 

     More details

    Event date: 1997.7

    Language:English  

  88. Fluid dynamic processes of diaphragm rupturing by a conically-nosed projectile

    Proceedings of the 21st International symposium on Shock Waves 

     More details

    Event date: 1997.7

    Language:English  

  89. Real-scale experimental simulation of tunnel sonic booms

    Proceedings of the 21st International symposium on Shock Waves 

     More details

    Event date: 1997.7

    Language:English  

  90. Operation tests of a 25-mm-bore ram accelerator

    ASME, SAE, and ASEE, Joint Propulsion Conference and Exhibit, 32nd, Lake Buena Vista, FL 

     More details

    Event date: 1996.7

    Language:English  

  91. Effect of finite rate chemical reactions on ram accelerator thrust characteristics

    ASME, SAE, and ASEE, Joint Propulsion Conference and Exhibit, 31st, San Diego, CA 

     More details

    Event date: 1995.7

    Language:English  

  92. Equilibrium and nonequilibrium radiation heat transfer over a reentry blunt body

    SAE, ASME, and ASEE, Joint Propulsion Conference, 26th, Orlando, FL 

     More details

    Event date: 1990.7

    Language:English  

  93. Steady-state permanent magnet MPD thruster

    DGLR, and JSASS, International Electric Propulsion Conference,19th, Colorado Springs, CO 

     More details

    Event date: 1987.5

    Language:English  

▼display all

KAKENHI (Grants-in-Aid for Scientific Research) 40

  1. Shock Wave Moderation by Fore-Flow Nudge: Proof of Principle and Applications

    Grant number:21H04589  2021.4 - 2025.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

      More details

    Authorship:Principal investigator 

    Grant amount:\42380000 ( Direct Cost: \32600000 、 Indirect Cost:\9780000 )

  2. Visualization measurement of plane shock wave - isotropic turbulence interaction and utilization of its statistical data

    Grant number:18H03813  2018.4 - 2021.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    Sasoh Akihiro

      More details

    Authorship:Principal investigator 

    Grant amount:\44460000 ( Direct Cost: \34200000 、 Indirect Cost:\10260000 )

    Interaction experiments were conducted in which the condition of the interacting states were independently changed using the originally developed "Counter-Driver Shock Tube". As a result of conducting the interaction experiments in which the shock wave Mach number, the turbulent flow Mach number, and the interaction distance were independently changed, it was shown that the interaction distance had a great influence on the deformation of the shock wave front, and the conventional concept of dealing with a steady state was found insufficient to describe the observed phenomena. From the experimental results, we were able to show the importance of introducing non-stationarity. It was shown that when the shock wave Mach number was relatively low and the turbulent Mach number was high, the shock wave front disappeared in the Schlieren image when the interaction distance was about 10 times or more of the integral scale. This fact was well explained by a model based on the Riemann problem.

  3. Conceptual Study of a Space Debris Deorbit Mission

    Grant number:16H02426  2016.4 - 2019.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    Ebisuzaki Toshikazu, TAKIZAWA Yoshiyuki, SAKAKI Naoto

      More details

    Authorship:Coinvestigator(s) 

    Space debris, in particular, cm-sized debris are important issue of space development. We performed a conceptual study for the deorbit mission by laser ablation with a high-intensity space-laser system. Among the steps of the deorbit operation of space debris, we performed the experiment of step 1; detection and step 2; tracking in the laboratory with 1/10 scale model of EUSO telescope. In addition, the optimization study revealed that the deorbit mission can work optimal condition in the sun-synchronous orbit, which can always stay in the twilight with the altitude of 600-900 km. Furthermore, we examined the ablation response for various debris materials and the way of the suppression of the rotation of them.

  4. Modulation and active control of supersonic flow by introducing artificial disturbance

    Grant number:15H02321  2015.4 - 2018.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    Sasoh Akihiro

      More details

    Authorship:Principal investigator 

    Grant amount:\44720000 ( Direct Cost: \34400000 、 Indirect Cost:\10320000 )

    In this study, we aimed in understanding mechanisms of supersonic flow modulation by artificial disturbances, and in developing their applications to supersonic flight. A counter-driver shock tube with a 120 mm * 120 mm square-cross-section was developed so that experiments of shock wave-turbulence interaction became possible. As a result, it was experimentally demonstrated that the longer the propagation distance the more the shock wave surface became disturbed, thereby leading to the topological transition of the wave front. Moreover, by introducing repetitive laser energy pulses on to Mach 1.9 flow, the shock wave oscillation experienced frequency modulation to a low frequency regime so that total pressure loss was reduced in a supersonic duct.

  5. Demonstration of thrust performance of helicon plasma electrostatic thruster

    Grant number:15K14250  2015.4 - 2016.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Exploratory Research

    SASOH Akihiro

      More details

    Authorship:Principal investigator 

    Grant amount:\3900000 ( Direct Cost: \3000000 、 Indirect Cost:\900000 )

    This study aimed in investigating the ion beam energy characteristics and ion beam current characteristics to optimize operation condition in helicon electrostatic thruster (HEST), which was an originally-developed, high-power, large-payload space propulsion thruster. With a low propellant flow rate, a ring anode whose inner diameter equaled that of the helicon plasma source exit yielded the best performance. In this case, the inner surface of the anode acted a primary role in the electrostatic acceleration. When the anode inner diameter bacome larger, the contribution of its side surface became larger; the electrostatic acceleration performance was much degraded when the side surface was covered with an insulator.

  6. Turbulence modulation simulation of sonic boom using field explosion experiments

    Grant number:26630442  2014.4 - 2015.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Exploratory Research

    SASOH Akihiro, YOKOTA Shigeru, SAKAI Yasuhiko, NAGATA Kouji, NAKAYAMA Yoshio

      More details

    Authorship:Principal investigator 

    Grant amount:\3900000 ( Direct Cost: \3000000 、 Indirect Cost:\900000 )

    In this study, experimental simulation method of evaluating overpressure variation induced by a blast wave interacting with turbulent flow was developed. The blast wave was generated using a 0.51-gram power. The turbulent flow was generated with an electrical fan, duct and grid. Overpressure histories were measured using four microphones set symmetrically. A 40 % standard deviation in overpressure was obtained, thereby demonstrating spatiotemporal behavior as the result of the shock wave-turbulence interaction.

  7. Process Clarification and Practical Realization of Direct In-situ Processing Method of Carbon Fiber Reinforced Thermoplastics

    Grant number:25220914  2013.5 - 2018.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (S)

    ISHIKAWA Takashi, YOSHIMIZU Daisuke

      More details

    Authorship:Coinvestigator(s) 

    An in-situ forming technique of carbon fiber reinforced thermoplastic (CFRTP) composites is studied, in which impregnation and lamination processes are operated simultaneously in a single manufacturing process. For this purpose, a manufacturing device which consists mainly of a diode laser and a compaction roller is developed. The results show that the bending modulus and strength of CFRTP fabricated by the present manufacturing device are as high as the ones obtained by a conventional hot press machine. A three-dimensional visualization method with high-speed stereo cameras is developed to analyze the deformation dynamics of CFRTP during the impact fracture. The obtained results suggest that the interfacial adhesion between carbon fiber (CF) and resin, and the property of resin strongly affect the impact fracture processes. Based on this observation, a new surface treatment for CF improving the impact strength is proposed for future application.

  8. 熱可塑CFRPの直接その場成形法の提案と破壊プロセスの解明

    Grant number:25249123  2013.4 - 2018.3

    科学研究費助成事業  基盤研究(A)

    石川 隆司, 佐宗 章弘, 池田 忠繁, 田邊 靖博, 酒井 武治

      More details

    Authorship:Coinvestigator(s) 

    (1)直接その場成形法の実現可能性評価及び(2)CFRTPの成形プロセスの解明に関しては、実験に使う繊維、樹脂の選定を始めた。特に、開繊糸とナイロンシートから なるセミプレグの観察および含浸時間評価、ホットプレスによるCFRTP成形 実験を行い、レーザーを用いたその場製造技術確立に資する試料データを取得した。また、真空バック樹脂含浸法でナイロン6のCFRTPを作製したところ、弾性率は予想値の8~9割であったが、強度は半分程度であり、含浸は上手くいっているが、繊維とナイロンと の密着が不足していると推察された。このため、サイジング剤及び表面処理剤の探索を開始した。
    (3)CFRPの破壊プロセスの解明に関しては、高速衝突試験装置の整備の 準備を始めた。
    25年度が最終年度であるため、記入しない。
    25年度が最終年度であるため、記入しない。

  9. Development of actively-controlled counter driver shock tube capable of precise flow control

    Grant number:25630390  2013.4 - 2014.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Exploratory Research

    SASOH Akihiro

      More details

    Authorship:Principal investigator 

    Grant amount:\3900000 ( Direct Cost: \3000000 、 Indirect Cost:\900000 )

    We have developed a shock tube with two counter drivers the condition to each of which can be set independently. From three criteria, (1) the effective diaphragm rupture time and associated shock wave formation distance, (2) pressure loss and flow uniformity, and (3) temporal jitter in the diaphragm rupture control were adopted to evaluate the driver performance. As the result, the device using an pneumatic cylinder was employed, thereby demonstration experiments including those for shock wave-turbulence interaction were conducted.

  10. Development of single-plate, two-wavelength Mach Zehnder interferometer for the measurement of unsteady density field with ionization

    Grant number:24656519  2012

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Exploratory Research

    SASOH Akihiro

      More details

    Authorship:Principal investigator 

    Grant amount:\4030000 ( Direct Cost: \3100000 、 Indirect Cost:\930000 )

    A new Mach-Zehnder interferometer, in which two interferograms with different wavelengths are imaged onto a single plate, has been developed. As light sources, semi-conductor lasers with the respective wavelengths of 473 nm and 593 nm are used. A dual-band-path filter is used to eliminate the effect of emission from ionized gas.The two-dimensional density distributions of heavy particles and electrons are obtained through digital data processing. Demonstration measurement was conducted with laser-pulse-generated plasma in a chamber of 350 mm in diameter and 400 mm in length, thereby obtaining a heavy particle density of 5×1025m-3and a degree of ionization of 10 % in the axi-symmetric field.

  11. Demonstration of tractor beam laser propulsion using aerodynamics effects

    Grant number:23656537  2011

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Exploratory Research

    SASOH Akihiro

      More details

    Authorship:Principal investigator 

    Grant amount:\4030000 ( Direct Cost: \3100000 、 Indirect Cost:\930000 )

    'Tractor beam' thrust is defined in laser ablation propulsion as generating a thrust in the direction toward a laser device. In order to demonstrate the feasibility of this technique, a torsion-type impulse stand with a high accuracy was designed and manufactured. Using this, the generation of a tractor beam thrust was demonstrated both in the atmosphere and in vacuum.

  12. Fly By Light Power: Improvement in High-Speed Aerodynamics with Low-Power Deposition

    Grant number:22226014  2010.4 - 2015.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (S)

    SASOH Akihiro, SAKAI Yasuhiko, SAKAI Takeharu, MATSUDA Atsushi, YOKOTA Shigeru, NAGATA Kouji

      More details

    Authorship:Principal investigator 

    Grant amount:\223730000 ( Direct Cost: \172100000 、 Indirect Cost:\51630000 )

    This study aimed for vastly improving supersonic aerodynamic performance by repetitive laser pulse energy depositions. The following results were obtained: (1) Utilizing the momentum production from the interaction between a shock wave and a laser-heated bubble, a wave drag reduction of higher than 20 % and an efficiency of energy deposition of 10 (1000%) were obtained. (2) It was demonstrated that boundary layer separation could be suppressed by the laser energy deposition onto shock wave-boundary interaction region. (3) A standard deviation of one order in magnitude larger than the average decrement in post-shock overpressure modulation past turbulence was obtained, thereby demonstrating the possibility of strongly influencing pressure fields even through weak spatiotemporal inputs.

  13. Search material components for developing high anti-impact behavior and easy machining

    Grant number:22560682  2010 - 2012

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

    TANABE Yasuhiro, UMEHAR Noritsugu, SASOH Akihiro

      More details

    Authorship:Collaborating Investigator(s) (not designated on Grant-in-Aid) 

    In this study, we conducted impact tests and investigated the effects of projectile materials on impact phenomena of CFRP by using three-dimensional (3D) measurement under high-velocity projectile impact. The following two were mainly revealed: the first is that
    (1) the ballistic limit range was affected by the kinetic energy of the projectile and this kinetic energy was proportional to the diameter of the projectile. When projectile was deformed, its deformation energy was not negligible small. The second is that
    (2) the main mechanism of energy absorption in CFRPs is their deformation. CFRPs, consisting of high-strength carbon fiber having large-failure-strain and deformable resin, could absorb large kinetic energy of a projectile. We can find a large trend that highly energy dissipated resins tended to show lower thrust-forces. Both of high resistivity against impact and easy-machining can be compatible in a CFRP.

  14. 超音速飛行におけるトランケイティッドコーン有用性の実証

    Grant number:21656221  2009 - 2010

    科学研究費助成事業  挑戦的萌芽研究

    佐宗 章弘

      More details

    Authorship:Principal investigator 

    Grant amount:\3200000 ( Direct Cost: \3200000 )

    本研究では,マッハ数2の超音速流れ中に置かれたトランケーティドコーン(円錐台,以下T-cone)の先端にレーザーパルスによるエネルギーを繰返し付与し,抗力低減と節約推進パワーが付与パワー量を上回る条件が両立する作動を実証し,今後の民間超音速飛行の実現に向けて一つの好材料を提供することを目標としている。平成21年度の実験は,JAXA宇宙科学研究本部(以下ISAS/JAXA)の超音速風洞を使用したが,天秤の分解能が本研究の目的のためには不測していることが判明し,抗力軽減特性データを取得できなかった。そこで,今年度は名古屋大学の吸込み風洞を用いて実験した。平成21年度末に繰返し周波数100kHzのパルスレーザーが導入されたので,それを活用して高繰返し効果によるバーチャルスパイク形成の実証と抗力軽減特性を取得した。高繰返しレーザーパルスを,風洞のBK7窓を通して試験部に導入し,モデルの内部を通さず直接モデル前方に集光させた。モデル形状(面積比,頂角)を固定し,レーザーパルスエネルギーと繰返し周波数を制御変数として,レーザーパワー付与したときの抗力測定実験を行った。その結果,レーザーパルスが誘起する高温・低密度領域と物体前方に形成される衝撃波との干渉によって生成される渦輪の作用によって,物体前方に低圧領域が滞留し,この渦輪の滞留時間を長くすることが,時間平均抗力低減に鍵を握ることがわかった。これは,トランケーティドコーンの先頭台部の面積を大きくするほど効果的であるが,反面ベースラインの抗力が低減した。先頭に台部を有しない形状,すなわち円錐では,レーザーパルスによる抗力低減量は小さく,パワー利得は1をはるかに下回る結果となった。さらに,台部を平面ではなく適切な曲率の凹面とすることによって,渦輪の滞留時間が増加し,抗力低減性能が向上することを実証した。

  15. Basic Study of Push-Pull Hybrid Propulsion

    Grant number:19206089  2007 - 2009

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    SASOH Akihiro, SAKAI Takeharu, MATSUDA Atsushi, MORI Koichi

      More details

    Authorship:Principal investigator 

    Grant amount:\41210000 ( Direct Cost: \31700000 、 Indirect Cost:\9510000 )

    This study aimed in the establishment of 'push-pull hybrid propulsion,' in which a small fraction of propulsion power is supplied to reduce a wave drag over a body in supersonic flow. We obtained an efficiency of energy deposition of up to 10. The drag reduction mechanisms, in which vortex rings generated by shock wavelaser-heated gas interaction played an important role were clarified.

  16. Fundamental Research for Silent Supersonic Transport Based on Supersonic Biplane Theory

    Grant number:19206086  2007 - 2009

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    OBAYASHI Shigeru, ASAI Keisuke, NAGAI Hiroki, SASOU Akihiro, KAWAZOE Hiromitsu, MATSUNO Takashi, NAKAHASHI Kazuhiro, MATSUSHIMA Kisa, JEONG Shinkyu, TSUBOI Nobuyuki, NAKAMURA Yoshiaki, MIYAJI Kouji, SATO Tetsuya, MATSUO Akiko, SAWAI Syujiro, FUJITA Kazuhisa, KOBAYASHI Hiroaki, TAGUCHI Hideyuki

      More details

    Authorship:Coinvestigator(s) 

    Supersonic Biplane Theory is a concept of eliminating wave drag and sonic boom by using shock wave interaction between two airfoils facing each other. The following research topics are investigated in this research to construct and validate the theory : Definition of three-dimensional wing configuration and its optimization, Investigation of low speed characteristics of supersonic biplane by using CFD and EFD, Supersonic wind tunnel test of starting process of three-dimensional supersonic biplane, Free flight experiment of supersonic biplane using ballistic range.

  17. Transdisciplinary Research for Silent Supersonic Aircraft by Integrating Computation and Experiment

    Grant number:15206091  2003 - 2006

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    OBAYASHI Shigeru, HAYASE Toshiyuki, SASOH Akihiro, SAITOH Tsutomu, NAKAHASHI Kazuhiro, MATSUSHIMA Kisa

      More details

    Authorship:Coinvestigator(s) 

    One of the fundamental problems preventing commercial transport aircraft from supersonic flight is the generation of strong sonic booms. The strength of the shock waves generated by an aircraft flying at supersonic speed is a direct function of both the aircraft's weight and its occupying volume; it has been very difficult to sufficiently reduce the shock waves generated by the heavier and larger conventional supersonic transport (SST) configuration to meet acceptable at-ground sonic-boom levels.
    Our team first re-analyzed the classic Busemann biplane configurations to understand its basic wave cancellation concept using modern Computational Fluid Dynamics (CFD) tools. We then designed a two-dimensional (2-D) supersonic biplane that not only shows the desired aerodynamic characteristics at its design condition, but also outperforms a zero-thickness flat-plate airfoil. (Zero-thickness plat-plate airfoils are known as the most efficient monoplane airfoil at supersonic speeds.) Also we studied biplane performance not only at their design Mach numbers but also at off-design conditions. We extended the analysis to 3-D wing configurations as well.
    In parallel to the computational studies, we carried out series of experiments. The first experiment conducted here was the sonic boom experiment using gas gun. The N-wave was captured successfully. The second experiment was the 2 D wind tunnel test using Indraft Wind Tunnel Facility newly constructed in this research. In addition, conventional wind tunnel tests were conducted using existing wind tunnels. These experiments revealed important off-design flow features to be further studies by using CFD.
    The main research result is the development of the supersonic biplane theory. Biplane configuration allows canceling shock waves created by supersonic objects. It can be unconventional and innovative concept for future supersonic transport.

  18. 火山爆発にともなう地表現象に対する新研究手法の開発と適用

    Grant number:14080203  2002 - 2006

    科学研究費助成事業  特定領域研究

    谷口 宏充, 今村 文彦, 佐宗 章弘, 後藤 章夫, 山田 功夫, 斎藤 務, 大島 弘光

      More details

    Authorship:Coinvestigator(s) 

    火山探査移動観測ステーション:当初に掲げた‘2km離れた地点からの無線操縦と観測データの送受信'は実現していることが確認されているので、本年度は、実際の噴火観測への運用を確実にするため、1986年の大島三原山の噴火推移に即してシナリオを作成し観測演習を行った。登坂走行や観測上の問題点などを明らかにしつつ、演習としてはおおむね満足すべき成果を得、実用への目処をつけた。火山観測用ドップラーレーダ:今年度はシステムを構成するデータ取得、処理系のプログラムの修正と改良を実施した。実際の火山噴火を対象とした試験観測をおこなうことは出来なかったが、野外における実験観測を通して実用化への目途をつけた。ヘリコプター投下型GPS観測システム:2005年10月浅間山において取得したデータに予期しないデータの欠落があり、これが測位解析結果の良くない原因であることが分かった。そこでデータの欠落があり、短く切れているデータを捨てたうえで再度解析を行ったところ、かなり改善された。火山爆発模擬実験装置:クレータ形成について、高圧ガスの駆動力と砂の挙動の力学的マッチングによってその飛散形態が大きく異なる観測結果をモデル化した。高圧ガス容器内の圧力履歴は一次元準定常ガス放出モデルで再現できること、砂の運動とガスの放出がマッチングするとドーム状の飛散形態となり、運動量交換が最大になることなどがわかった。火山性爆風数値計算コード:爆発的噴火による爆風の発生と伝播、そして火砕サージの流下過程を模擬する計算コードを開発してきた。昨年度で実際の地形をも考慮した、火砕サージの3次元数値模擬計算コード開発を行い、本年度は有珠火山と桜島火山などの火山を対象に数値実験を繰り返し、現象の再現は成功している。火山性津波数値計算コード:喜界カルデラ津波に対し、崩壊モデルや火砕流突入モデルなどを検討し、津波規模の推定解析を行った。

  19. Control of Mach number of Electromagnetically accelerated plasma flow using a magnetic nozzle and its applications

    Grant number:14208046  2002 - 2004

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    INUTAKE Masaaki, ANDO Akira, HATTORI Kunihiko, SASOH Akihiko, YOSHINUMA Mikirou

      More details

    Authorship:Coinvestigator(s) 

    This research aims to clarify an electromagnetic acceleration mechanism of plasma flow and to control Mach number of the plasma flow using a magnetic nozzle for optimization of the plasma acceleration. Especially, we have directly observed the electromagnetic force (Lorentz force) accelerating the plasma in the Laval-type magnetic nozzle and compared it with the flow velocity measurement. We investigated in detail the formation of the Lorentz force in various magnetic field configurations and effects on the acceleration. The results are summarized as follows.
    1.The thermal energy of the ion was converted into the flow energy by passing through the Laval type magnetic nozzle at the muzzle of Magneto-Plasma-Dynamic arcjet (MPDA). The ion Mach number of the plasma attains to more than unity and the supersonic plasma flow was obtained.
    2.Spatial profiles of the several plasma parameters, flow velocity, ion temperature and Mach number of the plasma, were consistent with the theoretical results derived from the one-dimensional isentropic flow model.
    3.It was experimentally clarified that the magnetic field in the plasma flow became weak caused by the diamagnetic effect and the converging magnetic field was spontaneously formed near the MPDA. The Lorenz force by the azimuthal current and the inward magnetic field decelerated ions in the plasma.
    4.Adding a strong diverging magnetic field improved the deformation of the magnetic field and changes the deceleration force to acceleration force, which resulted in a large increase of plasma flow velocity.
    As a result, we have shown that the electromagnetic force acting on the plasma flow could be controlled directly by shaping the external magnetic field, and clarified the plasma acceleration mechanism and its control methods.

  20. Study of physics and practical applications of laser-driven in-tube accelerator

    Grant number:13852014  2001 - 2005

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (S)

    SASOH Akihiro, TANIUCHI Tetsuo, KOBAYASHI Hideaki, SAWADA Keisuke, YAMAGUCHI Shigeru, HORISAWA Hideyuki

      More details

    Authorship:Principal investigator 

    Grant amount:\124280000 ( Direct Cost: \95600000 、 Indirect Cost:\28680000 )

    Basic and application studies were conducted on the laser-driven, in-tube accelerator which had been developed by the head investigator. The operation principle was experimentally validated in 4-m-high vertical launch experiment. The impulse generation mechanisms were experimentally and numerically studied by highlighting the interactions among shock waves, expansion waves and laser-generated plasma and accompanying fluid-dynamics instabilities. A scaling law of its propulsion performance was established. The impulse enhancement using laser ablation was experimentally demonstrated. Those are useful for practical applications. In this device, the momentum coupling coefficient, which is defined as the ratio of an impulse to a laser energy, can be tripled owing to a confinement effect and with appropriate setting of the working gas species and its fill pressure. The momentum coupling coefficient scales with the reciprocal of the speed of sound, which was experimentally validated using three kinds of monoatomic gases, argon, krypton and xenon. The secondary effect of their ionization potential on the impulse was also obtained. The impulse performance is uniquely characterized using a dimensionless momentum coupling coefficient, the dimensional momentum coupling coefficient multiplied by the speed of sound, and a dimensionless parameter, the ratio of the fill pressure multiplied by an effective projectile volume to the laser energy. From the experimental and numerical analysis, it is concluded that the impulse performance can be optimized from the effective expansion volume of the laser plasma. In the laser-ablative performance experiment, polyacetal exhibited the best performance ; its impulse is sensitive to the ambient pressure. At an appropriate laser fluence, the impulse becomes highest at ambient pressures below 100 Pa. This favorable performance can be useful not only for improving the propulsive performance of the device but also for other various space applications including space debris deorbiting.

  21. 複雑媒体中の衝撃波現象の解明と学際応用

    Grant number:12CE2003  2000 - 2004

    科学研究費助成事業  特別推進研究(COE)

    井小萩 利明, 高山 和喜, 林 一夫, 佐宗 章弘, 齊藤 務, 小原 拓, 谷口 宏充, 井小萩 利明, 樋口 博

      More details

    Authorship:Coinvestigator(s) 

    特別推進研究「複雑媒体中の衝撃波現象の解明とその学際応用」では、(1)複雑組成の媒体中の衝撃波現象、(2)化学変化、相変化を伴う媒体中の衝撃波現象、(3)複雑境界を過ぎる衝撃波、また、極低温および高温境界を過ぎる衝撃波、および(4)きわめて大きな時間変動を伴う衝撃波現象を解明し、その成果を医療、地球物理など学際領域研究に発展させ、また、産業応用への展開の基盤技術の確立を目指した。また、この本研究拠点が国内外に衝撃波学際応用研究センターとなることを目標に研究を推進した。ここに、過去および最近5年間の衝撃波研究の成果が体系化され、本拠点活動が国内の衝撃波研究会活動を支援するばかりでなく、平成17年3月に国際衝撃波学会(International Shock Wave Institute)の設立に結びついたこと述べ、特別推進研究「衝撃波」を総括する。主な研究成果は:
    i)基礎的研究くさびを過ぎる衝撃波反射に粘性効果に起因する遷移遅れを実験と精緻な数値模擬結果との対比から、始めて実証した。この現象が凹面および凸面さらに円錐面にも現れることを明らかにし、流体力学の教科書を書き直すに足る事実を見いだしている。また、大型縦型衝撃波管内に加速度計を内蔵した球を吊し衝撃波を負荷するという巧妙な実験で、衝撃波負荷での球の非定常抗力を実測し、衝撃波ないし爆風負荷での各種形状物体の非定常抗力計測に始めて成功している。この結果は数値模擬法との組み合わせで、粉塵気体中の衝撃波伝播に非定常抗力の効果明らかにしている。縦型無隔膜衝撃波管、大型無隔膜衝撃波管などを設計法を開発して、衝撃波の実験研究の精度を飛躍的に向上させ、また、衝撃波研究に微小爆薬の爆発を導入するなど、独創的な衝撃波実験法を発展させている。高性能の二段式軽ガス銃を設備し、弾道飛行実験装置の機能を加えて、高速飛行および高速衝突の動力学の体系化に成功している。直径1mのシュリーレン鏡を導入して大視野で、高レイノルズ数流れの二重露光ホログラフィー干渉計測定法を確立し、さらに、これを位相変位ホログラフィー干渉計法を展開し、音波に近い非常に弱い衝撃波の計測に成功している。気体、液体、混相媒体中の衝撃波現象の解明に適した数値模擬法を開発している。
    ii)水中衝撃波現象の解明とその医療応用 医学部の共同者と衝撃波の医療応用を推進し、衝撃波医療システムが構築されようとしている。水中でパルスレーザー光照射でのマイクロ衝撃波発生の物理を解明し、成果を種々の医療装置開発に結びつけることに成功している。カテーテル内でのレーザー光照射で気泡と衝撃波を発生し、カテーテル先端から直径0.1mm、速度20m/s程度の水ジェットを制御して噴出させ、これを空気中で用いて生体軟組織の切開装置を試作し、また、これを血管内で用いて低侵襲的な脳血栓血行再建術装置を試作している。これら装置での基礎実験、動物実験を終了させて現在臨床実験を開始しようとしている。また、衝撃波と細胞の相互作用を組織学的にまた生化学的に解明するための、医学と工学の連携研究が進行中である。パルスレーザー光を金属膜に作用させ発生するレーザーアブレージョンでの金属膜の高速変形を用いて微粒子を高速で打ち出す過程を詳細に解明して独創性の高いドラッグデリベリー法を開発している。この原理は微粒子分布と貫通深さを制御した物理的遺伝子導入法の開発に拡張され、現在、実用研究が進行中である。
    iii)地球物理、火山学への応用地球物理学者との連携で研究を推進し、地球進化史に巨大隕石衝突が重要な役割を果たし、そのとき固体および水中衝撃波が激変の素過程となっていることを、アナログ実験と数値模擬により様々の角度から実証している。また、火山の爆発的な噴火では短時間のエネルギー解放が重要な素過程となり、同様に衝撃波の関与が重要となっていることを実証している。特に、マグマの微粒化の動力学的機序をアナログ実験で解明した。
    iv)産業応用爆発騒音、自動車排気騒音およびトンネルソニックブームの機序を解明し、防止あるいは低減法を提案している。また、レーザー光を用いる新しい海底岩盤掘削法開発の基礎を確立した。
    v)学会活動5年間の拠点形成過程を通じて日本衝撃波研究会事務局を、また、Shock Wave International Journalの編集長と編集事務を担当し、さらに、拠点活動の一環として平成13年アジア太平洋衝撃波研究会を発足させ、これを平成17年3月国際衝撃波学会(International Shock Wave Institute)の設置に発展させている。

  22. Shock Dynamic Study of Laser Ablation Induced Drug Delivery

    Grant number:12355009  2000 - 2002

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    TAKAYAMA Kazuyoshi, SAITO Tsutomu, SASOH Akihiro, IKOHAGI Toshiaki, TAKAHASHI Akira, WADA Hiroshi

      More details

    Authorship:Coinvestigator(s) 

    In the Interdisciplinary Shock Wave Research Center, Tohoku University, we have aimed to apply the shock wave phenomena to medicine. We have already finished the extracorporeal shock wave lithotripsy and now are working for the development of system for revascularization of cerebral thrombosis, which is expected to be completed in very near future. In these topics a shock wave plays always an important role*. When a Q-switched laser beam focused a spot on a metal foil surface, instantaneously a plasma cloud ejected from the spot and as its reaction a shock wave is generated inside the metal foil which propagate and reflected from the other surface. The plasma formation is called laser ablation. The reflected wave an expansion one and as a result of it the foil is instantaneously bulged at 2 to 5 km/s. When small* particles are attached on the metal surface these would be ejected at such a high speed at the moment laser beam irradiation. This principle has been applied to accelerate dry drug particles or metal particles* of the order of magnitude of one micron or so into human tissue. We have used Q-switched Nd:YAG laser focused on the surface of a 5 mm thick glass plate backed up with 0.1 mm this aluminum foil on which tungsten or gold particles were attached. We measured the particle ejection speed to be in the order of magnitude of 1 to 2 km/s. Injecting these particles against agarose cell, mouse liver, and mouse skin, we measured penetration depths against these and found the maximum penetration depth was about 6 mm for individual materials. The free flight of such small particles belongs to hypersonic Stokes flow which has never be discussed seriously in the field gas dynamics. We have developed numerical scheme to estimate particle free flight as well as penetration into soft tissues. We have examined with this method the penetration into cell lines in liquid solution and observed a beautiful penetration of a one micron tungsten particle into a cell. Based on these basic studies we concluded that this method is superior to the existing mechanical gene delivery systems and so robust and compact that it can be redesigned as a therapeutic device. We believe we have accomplished our main goal which we proposed at first.

  23. 低リコイル大口径高速射出システムの実用開発

    Grant number:12555271  2000 - 2002

    科学研究費助成事業  基盤研究(B)

    佐宗 章弘, 生田 一成, 齋藤 努, 高山 和喜, 永易 伸生

      More details

    Authorship:Principal investigator 

    Grant amount:\1700000 ( Direct Cost: \1700000 )

    本年度の計画として、昨年度試作した低リコイル高速射出装置の推進性能実験の実績を基に、その作動条件の最適化をさらに進める予定であったが、平成13年7月31日付けで基盤研究(S)の内定によりこの課題を辞退することとなった。これまでの研究成果で、低リコイルの初段射出装置として、火薬と軽ガスを組み合わせたハイブリット方式にすることが有効であることがわかった。これは、軽ガスを火薬で駆動することによって、初期の充填圧力を低く保ったまま一時的な高圧状態を作り出すことができ、さらに駆動気体となるヘリウムの比熱比が高く原子量が小さいため、高い音速をもつことによって、駆動気体としての好ましい性質を有するためであることがわかった。また、二段目の加速部としてはラム加速が有効であり、これはこれまでラム加速機の研究実績により、実験データベースがかなり整えられている。今年度は、これらを組み合わせて二段作動システムを稼動させる予定でいたが、上記の理由によりそこまでには至らなかった。しかし、初段加速、ラム加速に関する研究成果は、アメリカ航空宇宙学会のJournal of Propulsion and Powerや2002年1月に開催された同学会年会で発表し、国際的にも高い評価を受けた。特に、初段加速部における隔膜破断圧の設定法や飛行体自体の、軽量化については独自のアイディアを実証している。このうち、飛行体の軽量化については、open-base方式を開発し、周囲が高圧であっても飛行体の強度を損ねることなく、高速まで加速が可能であることを実証している。なお、本研究で培った低リコイル高速射出技術は、新しく採択された基盤研究(S)において、超音速条件でのレーザー加速の実証実験の初段打ち出し装置へ応用される見通しとなっている。

  24. Basic research of the generation mechanism of aerodynamic noise

    Grant number:12450073  2000 - 2002

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    INOUE Osamu, MOCHIZUKI Osamu, ISHII Katsuya, NAKAMURA Yoshiaki, HATAKEYAMA Nozomu, FUKUNISHI Yu

      More details

    Authorship:Coinvestigator(s) 

    In this project, the generation and propagation mechanisms of aerodynamic noises generated by the motions of vortices and shock waves are investigated. We developed a highly-accurate finite difference numerical scheme (6-th order accurate in space and 4-th order in time) to solve the unsteady compressible Navier-Stokes equations. By applying the scheme to shock-vortex interaction problems, we found that noises are generated in response to the generation of reflected shock waves caused by the interaction, and that the generated reflected shock waves interact with vortices again and produce noises successively. This is an important finding on the mechanism of sound generation in supersonic turbulent flows. Next, we applied the scheme to the problems of aeolian tones generated by an obstacle in a uniform flow. The results showed that the generation frequency of the sound is equal to the fluctuation frequency of lift force and also to the shedding frequency of Karman vortices. We also found that the propagation of sound is affected by the Doppler effect and the propagation angle is determined by the Mach number. We also compared our numerical results with the prediction by Curle's acoustic analogy and pointed out that the Curle's analogy in its original form is incomplete and proposed an improved method which gives a close approximation to the correct solutions. We also proposed a new method which is effective to control actively the generation and propagation of aeolian tones generated by a circular cylinder in a uniform flow.

  25. 管内で加速する新しいレーザー推進法に関する基礎研究

    Grant number:12450391  2000 - 2002

    科学研究費助成事業  基盤研究(B)

    佐宗 章弘, 高山 和喜

      More details

    Authorship:Principal investigator 

    Grant amount:\7800000 ( Direct Cost: \7800000 )

    本年度の計画として、昨年までのレーザー駆動管内加速装置の試作、インパルス、圧力測定実験の基礎データ取得の実験を基に、垂直打上実験とその詳細な推進性能データを取得する予定であったが、平成13年7月31日付けで基盤研究(S)の内定によりこの課題を辞退することとなった。
    しかし、それまでの研究成果で本装置の作動が実際に可能であったことを実証することができ、さらに数値シュミレーションのための基礎データを取得することで、数値シュミレーションによる加速機構のより詳細なプロセスを明らかにすることができた。特に、管内に封入する作動気体の化学種や充墳圧力を変えることによって推進性能を制御できる点、管内での閉じ込め効果による性能向上、出口側からレーザー光を入射させる3点は、本研究のとくにアピールできる点であり、研究成果を外国の学会で発表し、本装置のオリジナリティーと実際に得られた推進性能について高い評価を得ている。この基礎研究は、将来の宇宙輸送システムに抜本的な改革をもたらす可能性を持っている。現在のロケットシステムは、ロケット本体に推進剤、酸化剤を搭載するため、特に打上げ時には、上空で使用する燃料/酸化剤を加速するために推力を出さねばならないというジレンマがある。これに対して、本研究のシステムは、作動気体は予め管内に封入しておくため、打ち上げコストを大幅に(1/10〜1/100)に削減できる可能性がある。また、飛行体の姿勢制御不要、レーザーに追尾機能搭載不要、レーザー光による周辺への危険性がなく、大気汚染、騒音の問題もない。近い将来、太陽光発電衛星からのレーザー光を利用した直接打上システム、軌道上での運動量発生システム、宇宙エレベータなどての実用展開の可能性も期待できる。これら基礎研究成果は、上記基礎研究(S)の研究課題に引き継がれ、実用展開を視野に入れたより高度な基礎研究に活用される見通しである。

  26. 極超音速衝撃波層における固体壁電気境界条件に関する研究

    Grant number:11875216  1999 - 2000

    科学研究費助成事業  萌芽的研究

    佐宗 章弘

      More details

    Authorship:Principal investigator 

    Grant amount:\1700000 ( Direct Cost: \1700000 )

    これまで、大気圏再突入に関わる流体の研究は、壁面の電気的な条件が考慮されずになされてきたものが殆どだった。ところが、超軌道速度での再突入では電離度が10%を越えることも有り得るため、プラズマ流体としての取扱いが必要になる。本研究では、その中の代表的な現象である、固体壁の電気境界条件について実験研究を行った。まず、イクスパンション管を用いた超軌道速度流れの発生法を確立した。実験室の限られた環境でそのような極限的な高エンタルピー流れを発生させるため、自由ピストン駆動部の条件をチューンドオペレーション法を改良することによって確立した。また、試験気流の状態を、従来の静圧、ピトー圧測定のみに頼らず、衝撃波層の高速度写真撮影、時間分解発光分光測定を通して、より精度よく測定した。特に、上記分光測定によって加速気体と試験気体の接触面を明確に測定し、許容誤差の関数として試験時間を評価した。淀み点エンタルピーは、最高37MJ/kgまで達成した。試験気流中に静電探針を置いてその浮遊電位を測定したところ、境界層の状態に依存して大きく変動することがわかった。また、二波長ホログラフィー干渉計法による円柱周りの衝撃波層の可視化実験を行い、浮遊電位金属壁、グランド電位金属壁、絶縁物壁による電子密度の違いを測定した。しかし、その差異は測定誤差の範囲内であり、電子境界条件がシース外部の流れ場に大きな影響をもたらす条件は見出せなかった。本研究の結論として、固体壁の電気境界条件は流れ場の大きな構造を変えるまでには至らないが、浮遊電位は大きく変動し、再突入物体の通信、計測機器への配慮が必要となることが示唆された。

  27. Study of real gas effects by using a Mach 20 hypersonic shock tube

    Grant number:10044119  1998 - 1999

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B).

    TAKAYAMA Kazuyoshi, SASOH Akihiro

      More details

    Authorship:Coinvestigator(s) 

    In simulating experimentally atmospheric re-entry of space vehicles, shock wave technology is best used to create high temperature conditions which are otherwise impossible to generate by any together methods. The high temperature so far appearing during the atmospheric re-entry exceed 10,000 K so that air molecules will dissociate and then ionized. This process is name real gas effect. The present study aims to experimentally verify the hypersonic real gas effect by using a 100 mm x 180 mm hypervelocity shock tube that has been transported from the Institute of Aerospace Studies, University of Toronto in 1994. The present study is to refurbish this shock tube by adopting a detonation driver system in which the reflection of detonation waves in stoichiometric oxyhydrogm mixture is used and to quantitatively visualize hypersonic shock waves using double exposure holography interferometry.
    The result obtained are summarized as following :
    (1) A diaphragmless operation system has been adopted successfully in this shock tube. Its characteristics have been throughly investigated. Its higher degree of repeatability that has not been achieved among existing shock tubes has been confirmed.
    (2) To ensure the initiation of detonations in the high pressure chamber, the transition from deflagration driven shock waves to detonation waves has been visualized using double exposure holographic interferometry. The effect of small particles shattering from the surface of micro-charges which initiate the chemical reaction.
    (3) Finite fringe holographic interferometry has been applied to the experiments in (2). Finite fringe interferograms were quantitatively analyzed by using Fourier fringe analysis. Its measuring system has been established.
    (4) Results obtained during two years of research works have been presented at international symposia. International collaboration with the Institute of Aerospace Studies, University of Toronto has been conducted.

  28. Study on dynamic mechanism of perforation on cancer cells at shock waves exposures

    Grant number:10450071  1998 - 1999

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    TAKAYAMA Kazuyoshi, HAYASHI Satoru, IORITANI Naomasa, SASHO Akihiro

      More details

    Authorship:Coinvestigator(s) 

    Extracoporeal shock wave lithotripsy (ESWL), non-invasive removal of kidney stones, is one of the most peaceful applications of shock waves. As a collaboration project with Medical School of Tohoku University we have developed prototype lithotriptor which was approved by the Ministry of Health and Welfare. As a result of basic research, tissue damages during ESWL treatments have been clarified and we found a technology to damage living tissue in a controlled fashion. This technology is extended to cancer research with the combination of chemotherapy during which it was discovered punctuation on the cancer cells when shock waves were exposed on them. The mechanism of punctuation is found to be related with shock wave interaction with nonhomogeneity of a medium with local curvature. The goal of present research is to clarify the mechanism of the punctuation in details.
    Results obtained are summarized as following :
    (1) Optical flow visualization of shock/tissue interaction has been developed. However, it has a limitiation in its spatial resolution. In order to compensate it, we seek for model tissues which have analogous characteristics to living tissues, with which various analogue experiments have been conducted and the results have been numerically simulated.
    (2) Finite fringe holographic interferometry has been developed and Fourier fringe analysis was well established. This method allowed to identify a slight density change created by shock wave exposures and was found to be effectively extended further shock/tissue interaction studies.
    (3) Numerical methods have been developed to be compared with experiments. Interactions between shock waves and various gas liquid interfaces have been successfully simulated.
    (4) A vertcal gas gun has been designed and constructed with which micro-shock/tissue interaction will be investigated. This is a facility which can directly simulate shock induced perforation on model tissue surface.

  29. Development of measuring systems of dissociated oxygen in hypersonic tunnel flows

    Grant number:09355034  1997 - 1999

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    TAKAYAMA Kazuyoshi, SUN Mingyu, SAITO Tsutomu, SASOH Akihiro

      More details

    Authorship:Coinvestigator(s) 

    Hypersonic wind tunnel flows can provide data base which would support entire Japanese space projects including HOPE-X and forth coming named space shuttle projects. In particular, to resolve heat shielding of re-entry space vehicles, the existing shock tube has to be upgraded to satisfy the generation of these extreme conditions.
    The aim of the present study is to develop the facility and measuring systems. Results obtained are summarized as following :
    (1) The high pressure chamber of a 100 mm x 180 mm shock tube has been modified to detonation driving operation systems and a quickly opening valve has been adopted to ensure higher degree of repeatability. Its characteristics are numerically and experimentally clarified.
    (2) The initiation of detonation waves was experimentally examined. A micro-charge ranging from 1.0 to 10 mg in weight was laser ignited in a detonation chamber, in order to clarify the transition from deflagration driven shock waves to detonation, in oxyhydrogen miters at initial pressure from 10 to 100 kPa. By using holographic interferometric observations, the boundary of initiations has been determined.
    (3)Starting processes in two-dimensional and axisymmetric nozzles have been numerically and experimentally investigated. In the case of an axisymmetric nozzle, an aspheric lens shaped converging and diverging nozzle was constructed and collimated object beam could pass without creating any distortion of images of test section, with which a quantitative image data acquisition became possible.
    (4) For the interpretation of experimental results, a dinette difference scheme using unstructured grids has been developed and a higher resolution has been obtained.

  30. "Advanced Application of Gas-dynamic to Planetary Exploration"

    Grant number:08305036  1996 - 1998

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    ABE Takashi, FUJIWARA Toshitaka, TAKAYAMA Kazuyoshi, NISHIDA Michio, SUZUKI Kojiro, HINATA M

      More details

    Authorship:Coinvestigator(s) 

    The extensive research was made on application of gas-dynamics on the future planetary exploration, mainly focusing on the reentry capsule which is planned for MUSES-C mission. MUSES-C mission planned by ISAS is to have a rendezvous with an asteroid and to bring back its soil to Earth. Since its reentry speed is quite high (-l3 km/sec), a variety of gas-dynamical problem must be resolved.
    In the present research, research effort was focused on the following main problems ; 1) the radiation efficient estimation from high temperature shock layer ahead of the vehicle, 2) the interaction of the high temperature air with the heat shield material of the vehicle, 3) the estimation of aerodynamic heat flux caused by highly-nonequilibrium high temperature shock layer. One of the main topics is the highly thermally-nonequilibrium phenomena, which is observed experimentally. This result is expected to have an impact on improving the current flow model, and to be helpful to improve the estimation accuracy by the improved flow model. Combining the results obtained from various topics, the aerodynamic heating along the flight path was successfully estimated, which was helpful to make a design requirement for such a reentry vehicle. In parallel, the possibility of the flight demonstration of such a reentry vehicle was studied.
    Other than the reentry vehicle, a study was conducted on the use of penetrator system for future planetary explanation, in a gas-dynamical point of view, This system study successfully clarified a design requirement of such a penetrator system. Also, the RAM accelerator system was studied, which is useful for the transportation of the exploration result from Moon. Even in a laboratory scale, the RAM accelerator was successfully demonstrated.

  31. Sound Generation by Interactions among Vortex, Heat and Shock Wave

    Grant number:08455086  1996 - 1997

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    INOUE Osamu, HATTORI Yuuji, JU Yiguang, SASOH Akihiro, FUKUNISHI Yuu

      More details

    Authorship:Coinvestigator(s) 

    Generation mechanism and natures of sound through vortex, heat and shock wave interactions are studied both computationally and experimentally. Inoue developped a highly-accurate, compressible Navier-Stokes code (6th-order in space and 4th-order in time) and applied it to shock-vortex interauction problems. The results show that, (1) three sounds are generated successively by the interaction between a single vortex and a plane shock wave, (2) each sound has a quadrupolar nature, and (3) the strengths of the sounds depend both on the strengths of a shock wave and a vortex. Inoue also applied the code to the interaction between a pair of vortices and a shock wave, and clarified that the number of sound generated by the interaction and the characteristic naturcs of the sounds depend on whether the pair of vortices moves in the same direction as the shock wave or opposite to it. Inoue also studied compressible flowfields around a helicopter and clarified the characteristic natures of the flowfields in a vortex ring state and in an autorotation state for the first time. The results suggest strongly that the sound generation in the helicopter rotor flowfield is closely related to the interaction between the tip-vortices and the rotor baleds. Fukunishi imposed a sound wave on a turbulent boundary layr, and examined the vortical motion in the boundary layr. Fukunishi found that the turbulent boundary layr can be effectively excited by the sound wave. Sasoh studied experimentally the sound noise at the exit of a tunnel produced by a highspeed bullet train (Shinkansen), and found that attenuation of a shock wave produced by a Shinkansen is inevitable to reduce the sound noise. Sasoh proposes the use of pseudo-perforated walls in a tunnel. By using a two-dimensional Navier-Stokes code, Ju studied numerically flowfields produced by the interaction of premixed gases of H2 and air with a shock wave, and found that the so-called Richtmyer-Meshkov instability plays an important role in the generation of vortices and thus the generation of sound. Hattori simulated numerically sound pressure fields generated by the head-on collision of two vortex rings, and found the following important results. (1) When the strengths of the two vortex rings are equal, two sounds are generated and each sound has quadrupolar nature. (2) When the strengths of the two vortex rings are not equal, four sounds are generated and the direction of the sound propagation is affected by the difference of the strengths of the two vortex rings. Hattori and lnoue also studied the characteristic natures of sound generated by oblique collisions of two vortex rings, and captured numerically the generation of octupolar sounds.

  32. Development of a small-sized ram accelerator for improving the muzzle velocity

    Grant number:08555239  1996 - 1997

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (A)

    SASOH Akihiro, KATO Yukio, TAKAYAMA Kazuyoshi

      More details

    Authorship:Principal investigator 

    Grant amount:\9200000 ( Direct Cost: \9200000 )

    In this study, the scaling effects were analyzed by conducting quasi-one-dimensional numerical simulation with finite-rate chemical reactions being taken into account. From the numerical simulation, it was concluded that in order to obtain a wide operation regime in the thermally-choked operation mode, small-sized apparatus was favorable. Based on this, a small sized ram accelerator was constructed and its operation tests were conducted. It was found that the smaller the apparatus the more difficult its starting became. In order to better understand the starting process, flow visualization experiments were conducted. The behavior of a precursory shock wave was visualized by using a high-speed image converter camera. Density field around a projectile impinging the diaphragm at the ram acceleration tube entrance was visualized by holographic interferometry, concluding that the existing diaphragm rupture model was inadequate in quantitative numerical simulation. By varying mixture components, fill pressure, powder mass, projectile configuration, sabot configuration and the initial pressure in the pre-acceleration section, ram acceleration experiments were done, obtaining a velocity gain of 370 m/s.

  33. STRUCTURE OF MIXING LAYER IN HIGH ENTHALPY HYPERSONIC FLOWS

    Grant number:07044116  1995 - 1997

    Grants-in-Aid for Scientific Research  Grant-in-Aid for international Scientific Research

    TAKAYAMA Kazuyoshi, SASOH Akihiro, SISLIAN Jean P.

      More details

    Authorship:Coinvestigator(s) 

    Topics on hypersonic turbulent mixing are not only basic research topics of high speed gas dynamics but also important applications of shock wave research. This international joint research program has been carried out for three years under close sollaborations between the Shock Wave Research Center Institute of fluid Science and the Institute of Aerospace Studies University Toronto.
    Results so far obtained are summarized as following :
    (1) A mathematical modelling of hypersonic turbulent mixing has been obtained by establishing a finite difference scheme which can handle three-dimentional Navies-Stokes equations in unstructured grid systems.
    (2) In order to include the chemical reaction terms in the above mentioned numerical scheme, detailed elementary processes of hedrogen-oxygen reactions has been investigated.
    (3) In conjunction with understanding of elementary processes of hypersonic turbulent mixsing, the motion of shock waves and flows behing them has been investigated experimentally and numerically.
    (4) The characteristic of a compact free piston shock tunnel and its contoured nozzle flow has investigated : piton motion in compression tube ; starting process of nozzle fow ; effect of diaphragm location on the nozzle flows ; Pitt pressure profile of nozzle flow ; driver gas contamination. Based upon these results, it is found that the contoured Mach 6 nozzle has a very limited working region so that a conical nozzle is designed for its replacement.
    (5) The stagnation enthalpy of 14 MA/kg and nozzle flow Mach number of 6 has been obtained. Double exposure holographic interferometric observation has been successfully applied to the flow over a cylinder.
    (6) The results have been obtained under close collaboration during the stay of Professor Jean Sislian for total 8 months from the fiscal years 1995 to 1997 and also the stay of Mr.Jurgen Schumacher for 6 month in 1997.
    (7) The results so far obtained are submitted for the publication in international journals having high reputation.

  34. Study on effects of chemical reaction rates on ram accelerator thrust performance

    Grant number:07651118  1995 - 1996

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

    SASOH Akihiro

      More details

    Authorship:Principal investigator 

    Grant amount:\2500000 ( Direct Cost: \2500000 )

    Numerical analyzes and ram accelerator operation experiments were conducted with the aim of clarifying relationships between its thrust performance and chemical reaction rates. There exist two propulsive modes in which subsonic combustion occurs ; subdetonative and transdetonative modes. In this study, numerical analyzes were based on quasi-one-dimensional steady flow with finite-rate chemistry taken into account. The formulation yields ordinal differential equations solution of which can be obtained through a well-developed implicit method. Instability in the calculation due to sonic singularity was avoided by a method which was developed uniquely in this study. The analyzes shows a propulsive mode is determined by the relationship between a characteristic length of finite-rate chemical reactions and a projectile length ; in a large apparatus the transdetonative propulsive mode tends to appear at relatively low Mach numbers. This result suggests that a small apparatus has an advantage to obtain stable subdetonative mode. For a large apparatus, a similar operation is possible by adjusting the fill pressure of the mixture. The experiments were conducted using a world-smallest working ram accelerator with a 25-mm-bore. As was predicted by the analyzes, ram acceleration was realized with a relatively energetic mixture. This study points out the importance of a chemical reaction induction length in determining the thrust performance. This conclusion should lead to further development of quantitative clarification of the scaling laws on ram accelerators.

  35. Study of Acoustic Sounds by Computational and Experimental Fluid Dynamics

    Grant number:06452172  1994 - 1995

    Grants-in-Aid for Scientific Research  Grant-in-Aid for General Scientific Research (B)

    INOUE Osamu, TSUBOTA Makoto, SASOH Akihoro, HAYASE Toshiyuki

      More details

    Authorship:Coinvestigator(s) 

    Acoustic sounds observed in four different fields of fluid dynamics are studied by four experts independently. Each expert in a field is supported by the other three experts in other fields who have different ideas, methods, know-hows and experiences, respectively. Inoue studied sounds produced by vortex-vortex interactions and shock wave-vortex interactions by 2D/3D direct Navier-Stokes simulations, and clarified the quadrupolar natures of sounds by the interactions. He also studied the 3D compressible flows around helicopter rotors and captured numerically vortex ring states and auto-rotation states for first time which are closely related to helicopter noises. Hayase studied numerically unsteady 2D flows in an orifice and also through spool valves, and showed that acoustic sound produced in these flows are closely related to the behavior of vortices. Sasoh studied experimentally tunnel sonic booms produced by highspeed trains, and showed that the booms are directly related to shock waves generated by entrance of a train in a long tunnel. Tsubota studied acoustic sounds in superfluid Helium and clarified that generation of quantized vortices is one of the sources of sounds in low temperature flow fields. The results obtained by the four experts are compared with each other. It is found that there are common natures among the sounds observed in spite of the difference of the flow fields studied ; for example, sounds produced by vortex-vortex interactions and vortex-sounds interactions have quadrupolar natures while dipolar property is predominant when obstacles or walls exist.

  36. Fundamental and Applicational Investigation of Ram Accelerator

    Grant number:05402033  1993 - 1995

    Grants-in-Aid for Scientific Research  Grant-in-Aid for General Scientific Research (A)

    TAKAYAMA Kazuyoshi, SASOH Akihiro, INOUE Osamu, NIOKA Takashi

      More details

    Authorship:Coinvestigator(s) 

    A ram accelerator system has been developed. The test section has a 25 mm bore and a 6m length. Its preaccelerator, a powder gun, is capable of launching a 40-gram payload to 1.2km/s with smokeless powder of 30 grams. The mixture supply system, composed of mass flow controllers and backpressure regulators, is easy to handle and utilizes cylinder pases up to a pressure about 1MPa higher than the fill pressure. Projectile velocity is measured by sensing magnetic induction using home made pick-up coils. The multiplexer system is capable of recording pressure data at plural points in one channel.
    Sixty ram acceleration experiments were made with methane-oxygen-nitrogen (or argon) mixtures. Sabot separation was made only by unsteady gas dynamics made in the mixture. Starting condition for ram acceleration strongly depended on non-dimensional heat release, entry speed and sabot design.
    A numerical code which can calculate the thrust performance based on the existing ram accelerator Hugoniot theory has been developed. Moreover, the theory was extended by taking finite-rate chemistry into account. With the extended theory, performances not only of the thermally choked mode but also of the transdetonative mode can be analyzed.
    It is important through this research project to show that ram acceleration is possible with this small bore apparatus, thereby enhancing understandings of scaling effects of ram accellerators. This technology is promising in being applied to space technology, material technology etc. in Japan.

  37. INVESTIGATION OF INTERNAL MECHANISM OF ELECTRIC THRUSTERS AND THEIR PERFORMANCE ANALYSIS

    Grant number:04302025  1992 - 1994

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Co-operative Research (A)

    ARAKAWA Yoshihiro, TOKI Kyoichiro, KIMURA Itsuro, FUJIWARA Toshitaka, NISHIDA Michio, YOSHIKAWA Takao

      More details

    Authorship:Coinvestigator(s) 

    In electric propulsion, there are several kinds of electric thrusters, such as electrostatic type, electromagnetic type and electrothermal type. The drawbacks common to the thrusters are ; 1)low energy conversion efficiency, 2)not demonstrated endurability for long operation, and 3)not obtained scaling laws determining thruster performance. To overcome these drawbacks, it is necessary to investigate physical phenomena in thrusters, Such-as ionization and dissociation processes, plasma acceleration mechanism, and heat and energy transport processes, not only by theoretical analysis but also by experimental one.
    For this purpose, this study has been continued for three years since 1992. It was a co-operative work of researchers and engineers of universities and research institutes, and had joint-meetings for several times, exchanging informations and discussing research contents and current topics.
    As the resuit, it was concluded that ; 1) in ion thrusters, numerical code has been constructed, which can be used to estimate thruster performance for given geometrical design and operating parameters, 2) as for arcjet thrusters, arc dischrage behaviors were examined and clarified both by experimental observations and by numerical calculations, 3) MPD flow analyzes have been conducted to obtain a further understanding of the relations between plasma flow and arc discharge, indicating that non-equilibrium flow plays an important role on inoization and plasma acceleration processes.

  38. Development of scaling law for radiative heat transfer from high enthelpyshock layrs

    Grant number:04650051  1992 - 1993

    Grants-in-Aid for Scientific Research  Grant-in-Aid for General Scientific Research (C)

    SASOH Akihiro

      More details

    Authorship:Principal investigator 

    Grant amount:\2000000 ( Direct Cost: \2000000 )

    Radiative heat transfer from non-equilibrium, high-enthalpy shock layrs generated around a blunt body has been studied. At Mach numbers from 25 to 35, the radiative heat transfer is mainly caused by strong radiative emission in a thermally and chemically non-equilibrium layr generated immediately behind the shock wave. According as an upstream Mach number increase, the intensity of the radiative emission sharply increases, resulting in sharp increase in the radiativeheat transfer. Under the above-mentioned condition, the thickness of the strong emission layr is almost independent of the nose radius. Hence, the radiative heat transfer is almost unchanged with the radius at such a low Mach number levels. At higher Mach number levels, radiative emission from a high-electron-density region near the wall become dominant. In this case, the radiative heat transfer increases with the dimensions of the body.

  39. 火山性ブラストの計測法の確立

    Grant number:04222110  1992

    科学研究費助成事業  重点領域研究

    藤井 直之, 谷口 宏充, 佐宗 章弘

      More details

    Authorship:Coinvestigator(s) 

    自然界の中でも最も大規摸な衝撃波現象の一つに爆発的噴水に伴う火山性ブラストがある。本研究では、火山性ブラストによる爆風圧やその伝播の把握のために、遠隔的に設置できかつ記録が可能な測定系、すなわち投下型・全方位指向性の爆風圧検出器について、実際の火山性ブラスト現象を解明するための計測法を確立するのを目的として共同研究を開始した。そのため、これまで衝撃波工学センターで開発され実用化されてきたピエゾセンサーによる圧力計を改良し、噴火口近傍でも設置でき測定可能な火山性ブラスト用の計測法の開発を行うことが、十分可能でかつ緊急の課題であると考えた。とくに火山性ブラストは、高温のガスと火山灰・噴石破片の混合物からなり、しかもその継続時間が通常の実験室内の衝撃波とは比較にならないほど長いと考えられるので、特別な工夫を必要とする。実用性のある火山性ブラスト用の計測系は、衝撃波の到来方向に無関係に設置できかつ安価・簡便なこと、耐熱性がありデータの記録を遠隔的にできることなどが必要条件である。本研究によって、まだ多少の改良点が必要ではあるが、このような条件に適合した十分実用に耐えうる圧力センサーと記録システムの開発見通しがたった。圧力センサーとしては、PVDFピエゾフィルムを貼ったステンレス製円筒の末端部の厚みによって、測定圧力範囲を調節できるものである。また、記録システムはSRAMに常時記録されたデータから、一定時間毎にトリガーレベル以上の信号を検出しDRAMにイベント毎に記録する方式が最適であると判断し、現在このシステムの試験をかねて、雲仙岳周辺で観測を行っている。今後は、さらに消費電流を少なくし、かつ簡便に設置できるシステムとデータの読みだしにテレメータ方式を採用する事など検討していく予定である。

  40. 高温化学反応を伴う衝撃波

    Grant number:02252109  1990

    科学研究費助成事業  重点領域研究

    藤原 俊隆, 佐宗 章弘, 久保田 弘敏, 斉藤 昊, 松為 宏幸

      More details

    Authorship:Coinvestigator(s) 

    デトネ-ションの研究に関しては、(i)斜めデトネ-ションの安定性と周期的振動の機構解明、(ii)逆制動ふく射を伝播機構とするレ-ザ-・デトネ-ションの可能性が調ベられた。これらは簡単化された化学反応に基いて解析された為、実際の現象が推測に基く機構から物理化学的に生じるかどうか、解析の結果は定性的に納得のゆく結論へ導く。即ち斜めデトネ-ションの振動は、局所的な爆発と壁から反射する圧力波間の相互干渉による共鳴現象である。炭酸ガスレ-ザ-を、水素分子やアルゴンガス中に、一平方ミリ当り10メガワットの強度で集光すると、球面レ-ザ-・デトネ-ションが伝播しそうである。
    衝撃波後方において、アセトアルドキシム及びホルムアルドキシムを熱分解し、生成物の挙動を調べた。二段階の単分子反応が起こる場合に、一段階目の反応の非平衡遷移状態構造が、二段階目の反応経路の選択を支配すると言う考えと同様に、分子の異性化についても検討がなされた。実験と反応分子動力学的計算の双方から、この事は言えそうである。
    その他松為、藤井、山崎らは、多くのラジカル反応に関して、衝撃波後方の高温下における、高速連鎖反応存在下に、速度定数を良い精度で計測した。この手法により、この迄全くと言っても良い程に手のつけられなかったラジカル反応が解明され、燃焼現象の制御や公害汚染物質の抑制に役立つ研究が行われる可能性を与えている。

▼display all

Industrial property rights 1

  1. アルコール-硝安発射薬

    佐宗章弘、高山和喜、生田一成、永易伸生、大坪信武

     More details

    Application no:特願平11-102098  Date applied:1999.4

    Country of applicant:Domestic  

 

Teaching Experience (On-campus) 9

  1. 宇宙推進工学

    2021

     詳細を見る

    宇宙での化学推進、非化学推進に関連する原理と応用について講義する。

  2. 航空宇宙推進工学

    2020

  3. Introduction to System Engineering

    2016

  4. Introduction to System Engineering

    2015

  5. Introduction to System Engineering

    2014

  6. Introduction to System Engineering

    2013

  7. Introduction to System Engineering

    2012

  8. Introduction to Production Engineering

    2011

  9. Introduction to System Engineering

    2011

▼display all