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Kiyonobu Otani

Section

Institute of Fluid Science

Job title

Specially Appointed Associate Professor(Research)

Degree

博士（工学）（室蘭工業大学）
修士（工学）（室蘭工業大学）

researchmap

https://researchmap.jp/read0156336

J-GLOBAL ID

201101074865361815

Research History 2

2017/04 - Present

Tohoku University　Institute of Fluid Science
2012/04 - 2017/03

Tohoku University　Institute of Fluid Science

Committee Memberships 33

火薬学会　第44期評議員

2024/04 - Present
日本衝撃波研究会　役員（事務局）

2024/04 - Present
高速度イメージングとフォトニクスに関する総合シンポジウム2026　組織委員会委員、実行委員会委員

2024/04 - Present
火薬学会　爆発安全専門部会委員

2022/05 - Present
Science and Technology of Energetic Materials　Editorial Board Member

2020/09 - Present
火薬学会　編集委員会委員

2020/09 - Present
火薬学会　爆発衝撃加工専門部会委員

2019/05 - Present
National Symposium on Shock Waves in Korea (NSSW Korea), Advisory Committee member

2018/02 - Present
日本機械学会材料力学部門所属研究会「材料力学における異分野融合に関する研究会(A-TS03-28)」　委員

2015/04 - Present
日本衝撃波研究会　2024年度衝撃波シンポジウム実行委員会実行副委員長

2024/10 - 2025/03
火薬学会　The 8th International Symposium on Energetic Materials and their Applications (ISEM2024) Program Committee member

2024/03 - 2024/11
日本衝撃波研究会　2023年度衝撃波シンポジウム実行委員会委員

2023/05 - 2024/03
火薬学会　第43期評議員

2022/04 - 2024/03
高速度イメージングとフォトニクスに関する総合シンポジウム2023　組織委員会委員、実行委員会委員

2023/02 - 2023/12
日本衝撃波研究会　2022年度衝撃波シンポジウム実行委員会委員

2022/09 - 2023/03
日本機械学会　M&M2022材料力学カンファレンス実行委員会委員

2021/09 - 2022/09
日本衝撃波研究会　2021年度衝撃波シンポジウム実行委員会委員

2021/10 - 2022/03
火薬学会　第42期評議委員

2020/04 - 2022/03
Japan Explosives Society　The 7th International Symposium on Energetic Materials and their Applications (ISEM2021) Program Committee member

2021/08 - 2021/11
日本混相流学会　評議員

2020/08 - 2021/08
日本衝撃波研究会　2020年度衝撃波シンポジウム実行委員会委員

2020/04 - 2021/03
日本衝撃波研究会　2019年度衝撃波シンポジウム実行委員会委員

2019/04 - 2020/03
日本衝撃波研究会　幹事

2016/03 - 2020/03
高速度イメージングとフォトニクスに関する総合シンポジウム2019　組織委員会委員、実行委員会委員

2019/02 - 2019/11
火薬学会　第41期評議委員

2018/04 - 2019/03
日本衝撃波研究会　平成30年度衝撃波シンポジウム実行委員会委員

2018/04 - 2019/03
日本衝撃波研究会　平成29年度衝撃波シンポジウム実行委員会実行委員長

2017/04 - 2018/03
火薬学会　The 6th International Symposium on Energetic Materials and their Applications (ISEM2017) Executive Committee member

2016/06 - 2017/11
日本衝撃波研究会　平成28年度衝撃波シンポジウム実行委員会委員

2016/04 - 2017/03
日本衝撃波研究会　平成27年度衝撃波シンポジウム実行委員会委員

2015/04 - 2016/03
高速度イメージングとフォトニクスに関する総合シンポジウム2015組織委員会　組織委員会委員

2015/04 - 2015/11
日本衝撃波研究会　平成26年度衝撃波シンポジウム実行委員会委員

2014/04 - 2015/03
日本機械学会部門協議会「高度物理刺激と生体応答に関する研究分科会(P-SCC12)」　委員

2013/04 - 2015/03

Show all ︎Show first 5

Professional Memberships 5

日本衝撃波研究会
JAPAN EXPLOSIVES SOCIETY
THE JAPANESE SOCIETY FOR MULTIPHASE FLOW
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
THE JAPAN SOCIETY OF MECHANICAL ENGINEERS

Research Areas 2

Aerospace, marine, and maritime Engineering / Aerospace engineering / Supersonic, Shock Wave
Manufacturing technology (mechanical, electrical/electronic, chemical engineering) / Fluid engineering /

Awards 5

火薬学会2015年度秋季研究発表会特別賞

2015/12　火薬学会　生体模擬物質の衝撃波伝播挙動
平成27年度静電気学会論文賞受賞

2015/11　静電気学会　水中正ストリーマの進展開始電圧に及ぼす放電パラメータの影響
高速度イメージングとフォトニクスに関する総合シンポジウム2015 Junior Researcher Award

2015/11　高速度イメージングとフォトニクスに関する総合シンポジウム2015組織委員会
平成18年度衝撃波シンポジウム Best Presentation Award

2008/03　平成18年度衝撃波シンポジウム実行委員会　パルスHo:YAGレーザ誘起液体ジェットを用いた岩石破壊実験
高速度撮影とフォトニクスに関する総合シンポジウム2007 Junior Researcher Award

2007/11　高速度撮影とフォトニクスに関する総合シンポジウム2007組織委員会

Papers 91

Partial heat curing enhancing space debris shielding performance in multi-layered inflatable structures Peer-reviewed

Hikaru Takahashi, Yoshihiro Sugiyama, Ryo Kuzuno, Sunao Hasegawa, Kiyonobu Ohtani, Yushin Hara, Kanjuro Makihara

Journal of Space Safety Engineering　2025/05
Publisher: Elsevier BV
DOI： 10.1016/j.jsse.2025.04.002 　

ISSN： 2468-8967
Study on non-Rankine-Hugoniot zone in axisymmetric supersonic flow Peer-reviewed

Yoshitaka Higa, Masanobu Matsunaga, Hideaki Ogawa, Kiyonobu Ohtani, Taro Handa

Physics of Fluids　37　(5)　2025/05/01
Publisher: AIP Publishing
DOI： 10.1063/5.0267059 　

ISSN： 1070-6631

eISSN： 1089-7666

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The non-Rankine–Hugoniot zone is known as an area that appears behind the location of axisymmetric shock-wave reflection where pressure is higher than that predicted from the Rankine–Hugoniot relation. In this study, the underlying mechanism of the non-Rankine–Hugoniot zone in axisymmetric shock-wave reflection is investigated experimentally and computationally. In the experiments, the flow with axisymmetric shock-wave reflection is created by using a ring wedge placed in a freestream at a Mach number of 2.5 (M∞ = 2.5) to visualize the shock system formed downstream using a planar laser-induced fluorescence technique. The shapes of the visualized shock waves are used to validate the computational results obtained by solving the Navier–Stokes equations numerically with an adaptive mesh refinement technique, which can capture the phenomena in the vicinity of the reflection point with a high spatial resolution. The validated computational results have indicated the existence of a non-Rankine–Hugoniot zone behind the Mach disk. It has also been revealed that heat conduction occurs across the boundary between the two flows that have passed different shock waves among the three shock waves resulting from axisymmetric shock-wave reflection, i.e., one has gone through the Mach disk, whereas the other has passed through the incident and reflected oblique shock waves. The appearance of the non-Rankine–Hugoniot zone can be explained reasonably by considering that the thermal state of the cooling flow behind the Mach disk has changed along the Rayleigh line.
Support Vector Machine Framework for Detecting Ambiguous Contours of Space Debris Cloud Peer-reviewed

Daisuke Morimoto, Hikaru Takahashi, Yoshihiro Sugiyama, Keisuke Otsuka, Kiyonobu Ohtani, Sunao Hasegawa, Kanjuro Makihara

Journal of Spacecraft and Rockets　62　(2)　528-541　2025/03
Publisher: American Institute of Aeronautics and Astronautics (AIAA)
DOI： 10.2514/1.a35927 　

ISSN： 0022-4650

eISSN： 1533-6794

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Operational spacecraft are prepared for collisions with space debris by installing protective walls (bumpers). A group of vaporized and liquefied microparticles generated by debris collisions is called a debris cloud. To evaluate the protective performance of bumpers, it is important to measure the spread velocity and angle of the debris cloud. However, debris cloud images exhibit ambiguous contours of debris clouds. Consequently, measurement errors in the spread velocity and spread angles occur because of the observer’s subjectivity. Commonly used derivative-based methods can detect steep contours; however, they cannot detect ambiguous contours such as those of debris clouds. In this study, a method for uniquely detecting the ambiguous contours of a debris cloud based on supervised machine learning and a continuous wavelet transform (CWT) is proposed. Feature points that indicate candidate points of the debris cloud contour are extracted using a method based on CWT. Four types of specific features for debris cloud contours were assigned to the feature points. Supervised machine learning using a support vector machine can detect the debris cloud contours. The proposed method enables the evaluation of the ambiguous contours of a debris cloud and the protection performance of a bumper without observer subjectivity.
Shape Keepers of Hollow Cylindrical Electrodynamic Tethers for Space Debris Removal International-journal Peer-reviewed

Yushin Hara, Ryo Kuzuno, Hikaru Takahashi, Yoshihiro Sugiyama, Yuki Kikuji, Kiyonobu Ohtani, Sunao Hasegawa, Kanjuro Makihara

Journal of Spacecraft and Rockets　2025/02/17

DOI： 10.2514/1.A36222 　
Three-dimensional density measurement around a Hayabusa re-entry capsule model in the ballistic range Peer-reviewed

Masato Yamagishi, Masanori Ota, Kiyonobu Ohtani, Hiroki Nagai

Experiments in Fluids　66　(1)　2024/12/27
Publisher: Springer Science and Business Media LLC
DOI： 10.1007/s00348-024-03943-5 　

ISSN： 0723-4864

eISSN： 1432-1114

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Abstract Three-dimensional density measurement around a Hayabusa re-entry capsule model using the background-oriented schlieren (BOS) technique is carried out in the ballistic range at the Institute of Fluid Science, Tohoku University. A Hayabusa re-entry capsule model with a diameter of 15 mm is used for a projectile, and the Mach number was 1.20. A method of model Position and Pose detection from BOS images was proposed for a capsule model, and unsteady flow field measurement around a free-flight test model was conducted. From the results, we succeeded in measuring the three-dimensional density distribution around a capsule model and visualizing the detailed structure in the wake region.
A shock-stable rotated-hybrid Riemann solver on rectangular and triangular grids Peer-reviewed

Sutthisak Phongthanapanich, Anirut Matthujak, Kiyonobu Ohtani, Elvin J. Moore

Physics of Fluids　36　(4)　2024/04/02
Publisher: AIP Publishing
DOI： 10.1063/5.0196510 　

ISSN： 1070-6631

eISSN： 1089-7666

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The rotated Riemann solver is robust against the carbuncle phenomenon, especially for multidimensional computation. Moreover, hybrid techniques are usually used to enhance the stability of an accurate scheme by combining an accurate scheme with a diffusive scheme. This paper proposes a rotated-hybrid Riemann solver named the rotated-HLLC+ scheme. The scheme is developed by hybridizing the Harten–Lax–van Leer contact (HLLC) scheme with the advection upstream splitting method based on a flux vector splitting (AUSMV+) scheme by following the rotated Riemann solver approach. The unit vector n1 is calculated from the velocity-difference vector, and the unit vector n2 is the orthogonal vector. The linearized analysis suggests that the HLLC scheme should be used in the direction of n1 and the AUSMV+ scheme in the direction n2. In this way, the hybrid scheme becomes shock-stable with less numerical dissipation. Moreover, the pressure-based method is used to detect the shock wave. Several numerical experiments suggest that the pressure cutoff parameter εp=0.01 may be generally suitable and provide a stable solution with little additional numerical dissipation. The last two numerical examples show that the computational performance of the rotated-HLLC+ scheme is comparable to the HLLC scheme for the weak shock reflection over convex double wedges. However, the scheme is approximately 9% faster than the HLLC scheme for the double Mach reflection of a strong shock wave. The proposed scheme gives fast, stable, and accurate solutions on rectangular and triangular grids.
Blast-induced Traumatic Brain and Craniofacial Injury: Clinical Manifestation, Diagnosis and Treatment in the Emergency Room Invited Peer-reviewed

口腔顎顔面外傷, 日本口腔顎顔面外傷学会誌

J. Jpn. Soc. O.M.F. Trauma　22　(1)　1-5　2023/09/14

DOI： 10.24787/jsomft.22.1_1 　
Accurate and Robust Hybrid HLLC Riemann Solver on Triangular Grids International-journal Peer-reviewed

Sutthisak Phongthanapanich, Anirut Matthujak, Kiyonobu Ohtani

AIAA Journal　61　(9)　2023/06/01

DOI： 10.2514/1.J062649 　
High Speed Visualization Measurement of Underwater Shock Wave and Cavitation Bubble Generation Invited

Kiyonobu Ohtani

Nagare　42　17-22　2023/02/25
Methodological assessment of the reduction of dissemination risk and quantification of debris dispersion during dissection with a surgical aspirator. International-journal Peer-reviewed

Sosuke Kageyama, Atsuhiro Nakagawa, Tomohiro Kawaguchi, Kiyonobu Ohtani, Toshiki Endo, Manabu Kyan, Tetsuya Kusunoki, Yoshiteru Shimoda, Shin-Ichiro Osawa, Masayuki Kanamori, Kuniyasu Niizuma, Teiji Tominaga

BMC research notes　15　(1)　279-279　2022/08/15

DOI： 10.1186/s13104-022-06167-0 　
Numerical study on a blast mitigation mechanism by a water droplet layer: Validation with experimental results, and the effect of the layer radius Peer-reviewed

Yuta Sugiyama, Takahiro Tamba, Kiyonobu Ohtani

Physics of Fluids　34　(7)　076104-076104　2022/07
Publisher: AIP Publishing
DOI： 10.1063/5.0091959 　

ISSN： 1070-6631

eISSN： 1089-7666

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This study explored the practicality of a two-phase flow model for water droplets in elucidating the blast mitigation mechanism of water droplets. To validate the model, the numerical data were compared with previous experimental results in terms of the evaporation of a single water droplet, and the interaction between the shock/blast waves and water droplets. Results of the validation confirmed good agreement and consistency between both data by combining the existing models for droplet breakup. Next, the blast-mitigation effect of water droplets sprayed around a high explosive was investigated, where the main parameter was the layer radius. A thicker layer further mitigated the blast wave, but there was a limit to the blast-mitigation effect when the layer radius was greater than a critical value. The high-temperature and high-pressure detonation products should interact with the water droplets, which absorb their momentum and energy. The critical layer radius was equivalent to the dispersion distance of the detonation products. To quantitatively understand the blast-mitigation mechanism of water droplets, the transferred energies by drag force, convective heat transfer, radiative heat transfer, and evaporation were computed. A strong correlation between the blast wave strength and the sum of transferred energies by the drag force and convective heat transfer was obtained in the case that the initial diameter of the water droplets was of the order of millimeters.
Observation of the Formation of Multiple Shock Waves at the Collapse of Cavitation Bubbles for Improvement of Energy Convergence Peer-reviewed

Marc Tinguely, Kiyonobu OHTANI, Mohamed Farhat, Takehiko Sato

Energies　15　(7)　2305-2305　2022/03
Publisher: MDPI AG
DOI： 10.3390/en15072305 　

eISSN： 1996-1073

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The collapse of a cavitation bubble is always associated with the radiation of intense shock waves, which are highly relevant in a variety of applications. To radiate a strong shock wave, it is necessary to converge energy at the collapse, and understanding generation processes of multiple shock waves at the collapse is a key issue. In the present study, we investigated the formation of multiple shock waves generated by the collapse of a laser-induced bubble. We used a high-speed imaging system with unprecedented spatiotemporal resolution. We developed a triggering procedure of high precision and reproducibility based on the deflection of a laser beam by the shockwave passage. The high-speed videos clearly show that: (A) a first shockwave is emitted as the micro-jet hits the bottom of the bubble interface, followed by a second shock wave due to the collapse of the remaining toroidal bubble; (B) a sequential collapse of elongated bubbles, where the top part of the bubble collapses slightly before the bottom of the bubble; and (C) the formation of compression shock waves from multiple sites on a toroidal bubble.
Measurement of unsteady shock standoff distance around spheres flying at Mach numbers near one Peer-reviewed

T. Kikuchi, K. Ohtani

Shock Waves　32　235-239　2022/01/24
Publisher: Springer Science and Business Media LLC
DOI： 10.1007/s00193-021-01067-x 　

ISSN： 0938-1287

eISSN： 1432-2153

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<title>Abstract</title>This paper reports the experiments on the shock standoff distance (SSD) around spheres flying at Mach numbers from slightly below 1.0. Spheres of the same diameter but three different densities were launched in a ballistic range by a light-gas gun, and the flow field around each sphere was measured by optical visualization. The purpose of this study is to investigate how projectile deceleration influences the SSD by comparing the results for projectiles of the same shape, size, and Mach number but different densities. The location history of the sphere center is obtained by fitting a formula derived from the equation of motion of a decelerating object, and the history of the instantaneous projectile Mach number is obtained by differentiating this formula.The SSDs of the projectiles with different densities are the same at higher Mach numbers, but different at lower Mach numbers, and the SSD decreases with decreasing projectile density. Seemingly, because projectile deceleration is related to the flow unsteadiness, steady flow cannot be assumed in the present range of Mach number with the different SSDs. At Mach numbers close to one, that of the propagating detached shock wave is higher than that of the flying projectile.
Schlieren Visualization and Motion Analysis of an Isolated and Clustered Particle(s) after Interacting with Planar Shock Peer-reviewed

Takayuki NAGATA, Taku NONOMURA, Kiyonobu OHTANI, Keisuke ASAI

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES　65　(4)　185-194　2022
Publisher: Japan Society for Aeronautical and Space Sciences
DOI： 10.2322/tjsass.65.185 　

ISSN： 0549-3811

eISSN： 2189-4205
Quantitative density measurement of wake region behind reentry capsule (Improvements in accuracy of 3D reconstruction by evaluating the view-angle of measurement system) Peer-reviewed

Masato YAMAGISHI, Yusuke YAHAGI, Masanori OTA, Yusuke HIROSE, Shinsuke UDAGAWA, Tatsuro INAGE, Shigeya KUBOTA, Koji FUJITA, Kiyonobu OHTANI, Hiroki NAGAI

Journal of Fluid Science and Technology　16　(3)　JFST0021-JFST0021　2021/10

DOI： 10.1299/jfst.2021jfst0021 　

ISSN： 1880-5558

eISSN： 1880-5558
Study on Shock Wave Pressure Attenuation by Shock Wave Interaction with Water Droplets Peer-reviewed

Kiyonobu OHTANI, Toshihiro OGAWA, Yuta SUGIYAMA, Takahiro TAMBA

JAPANESE JOURNAL OF MULTIPHASE FLOW　35　(2)　302-307　2021/04/15
Publisher: The Japanese Society for Multiphase Flow
DOI： 10.3811/jjmf.2021.005 　

ISSN： 0914-2843

eISSN： 1881-5790
Comparison of blast mitigation performance between water layers and water droplets Peer-reviewed

T. Tamba, Y. Sugiyama, K. Ohtani, K. Wakabayashi

Shock Waves　31　(1)　89-94　2021/01

DOI： 10.1007/s00193-021-00990-3 　

ISSN： 0938-1287

eISSN： 1432-2153
Damage Assessment for Electrodynamic Tape Tether against Space Debris Impact Peer-reviewed

Michihiro FUJIWARA, Honoka TOMIZAKI, Sunao HASEGAWA, Kiyonobu OHTANI, Kanjuro MAKIHARA

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN　19　(1)　34-41　2021
Publisher: Japan Society for Aeronautical and Space Sciences
DOI： 10.2322/tastj.19.34 　

eISSN： 1884-0485
Damage of twisted tape tethers on debris collision Peer-reviewed

Yoshiyuki Uwamino, Michihiro Fujiwara, Honoka Tomizaki, Kiyonobu Ohtani, Kanjuro Makihara

International Journal of Impact Engineering　137　103440-103440　2020/03
Publisher: Elsevier BV
DOI： 10.1016/j.ijimpeng.2019.103440 　

ISSN： 0734-743X
Experimental investigation of transonic and supersonic flow over a sphere for Reynolds numbers of 103–105 by free-flight tests with schlieren visualization Peer-reviewed

T. Nagata, A. Noguchi, T. Nonomura, K. Ohtani, K. Asai

Shock Waves　30　(2)　139-151　2020/03
Publisher: Springer Science and Business Media LLC
DOI： 10.1007/s00193-019-00924-0 　

ISSN： 0938-1287

eISSN： 1432-2153
blast-induced traumatic brain injury (bTBI): 損傷機序と病態 Peer-reviewed

Nakagawa Atsuhiro, Ohtani Kiyonobu, Yagihashi Mao, Sakuma Atsushi, Tomita Hiroaki, Karibe Hiroshi, Armonda Rocco, Kushimoto Shigeki, Tominaga Teiji

NEUROSURGICAL EMERGENCY　25　(2)　195-202　2020
Publisher: Japan Society of Neurosurgical Emergency
DOI： 10.24723/jsne.25.2_195 　

ISSN： 1342-6214

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A blast wave (BW) is generated by an explosion and is comprised of a lead shock wave followed by a supersonic flow. In addition to civilian traumatic brain injury (TBI) mechanisms, pressure‒induced damage accounts for the occurrence of blast‒induced TBIs (bTBIs). Fracture, hemorrhage, massive and rapid edema progression, and cerebral vasospasm are the characteristic clinical findings of bTBI in the acute phase, and in the chronic period the characteristic clinical findings are cognitive dysfunction and posttraumatic disorder. Since a BW is invisible and impacts the brain within an extremely short period of time (in contrast to direct‒impact and penetrating mechanism injuries), the victim may not immediately realize that s/he has suffered clinically. There have been few animal models that can be examined in the laboratory and validated in terms of shock wave (SW) physics, and this has hampered the understanding of the mechanisms and pathophysiology of bTBIs. At the Institute of Fluid Science, we have successfully formed organized infrastructures and accumulated knowledge concerning SWs and BWs since the 1980s for both engineering issues and medical applications. Here, we describe the pathophysiology and the mechanisms underlying bTBIs and the current research tasks in the field of SW physics. We also describe the diagnoses of blast injury patients and their treatment.
Experimental investigation of blast wave pressure mitigation by water droplets interaction Peer-reviewed

Takahiro Tamba, Yuta Sugiyama, Kiyonobu Ohtani, Kunihiko Wakabayashi

Science and Technology of Energetic Materials　81　(1)　29-32　2020
プラズマファインバブルの生成と計測 Peer-reviewed

佐藤岳彦, 上原聡司, 熊谷諒, 宮原高志, 大泉雅伸, 中谷達行, 落合史朗, 宮崎孝道, 藤田英理, 金澤誠司, 大谷清伸, 小宮敦樹, 金子俊郎, 中嶋智樹, ティンガリー・マーク, ファーラット・モハメッド

混相流　33　(4)　382-389　2019/12
Formation of fine bubbles by plasma in water Peer-reviewed

Takehiko Sato, Ryo Kumagai, Takashi Miyahara, Masanobu Oizumi, Tatsuyuki Nakatani, Shiroh Ochiai, Takamichi Miyazaki, Hidemasa Fujita, Seiji Kanazawa, Kiyonobu Ohtani, Atsuki Komiya, Toshiro Kaneko, Tomoki Nakajima, Marc Tinguely, Mohamed Farhat

International Journal of Plasma Environmental Science & Technology　12　(2)　44-48　2019/01
Biological effect of shock waves: Mechanism of Blast-Induced Traumatic Injury to Medical Application Peer-reviewed

Nakagawa A, Ohtani K, Kawaguchi T, Tominaga T.

31st International symposium on Shock Waves 2　2　421-429　2019
The quantitative density measurement of unsteady flow around the projectile Peer-reviewed

Y. Hirose, K. Ishikawa, Y. Ishimoto, T. Nagashima, M. Ota, S. Udagawa, T. Inage, K. Fujita, H. Kiritani, K. Fujita, K. Ohtani, H Nagai

Journal of Flow Control, Measurement & Visualization　7　(2)　111-119　2019
Experimental and numerical study on radiating shock tube flows for spacecraft reentry flights Peer-reviewed

Gouji Yamada, Mizuki Kajino, Kiyonobu Ohtani

Journal of Fluid Science and Technology　14　(3)　JFST0022　2019

DOI： 10.1299/jfst.2019jfst0022 　

eISSN： 1880-5558
Propagation and branching process of negative streamers in water Peer-reviewed

R. Kumagai, S. Kanazawa, K. Ohtani, A. Komiya, T. Kaneko, T. Nakajima, T. Sato

Journal of Applied Physics　124　163301-1-163301-7　2018/10

DOI： 10.1063/1.5025376 　
Surface pressure measurement on supersonic free-flight projectiles using unsteady PSP techniues

Daiju Numata, Kiyonobu Ohtani

2018 Aerodynamic Measurement Technology and Ground Testing Conference　2018
Publisher: American Institute of Aeronautics and Astronautics Inc, AIAA
DOI： 10.2514/6.2018-3315 　
Jetting from cavitation bubbles due to multiple shockwaves Peer-reviewed

O. Supponen, T. Akimura, T. Minami, T. Nakajima, S. Uehara, K. Ohtani, T. Kaneko, M. Farhat, T. Sato

Applied Physics Letters　113　193703-1-193703-4　2018
Primary blast-induced traumatic brain injury: lessons from lithotripsy Peer-reviewed

A. Nakagawa, K. Ohtani, R. Armonda, H. Tomita, A. Sakuma, S. Mugikura, K. Takayama, S. Kushimoto, T. Tominaga

SHOCK WAVES　27　(6)　863-878　2017/11

DOI： 10.1007/s00193-017-0753-5 　

ISSN： 0938-1287

eISSN： 1432-2153
Propagation analysis of negative streamer channel in water

Ryo Kumagai, Seiji Kanazawa, Kiyonobu Ohtani, Atsuki Komiya, Toshiro Kaneko, Tomoki Nakajima, Takehiko Sato

Proceedings of 23rd International Symposium on Plasma Chemistry (ISPC-23)　2017/07/30
Visualization of inception, propagation and collapse process of underwater positive streamer Peer-reviewed

Takehiko Sato, Ryo Kumagai, Tomoyuki Nakajima, Kiyonobu Ohtani, Atsuki Komiya, Seiji Kanazawa, Toshiro Kaneko

Proceedings of the 31st International Symposium on Shock Waves (ISSW31)　2017/07/09
Experimental demonstration of bow-shock instability and its numerical analysis Peer-reviewed

Y. Kikuchi, N. Ohnishi, K. Ohtani

SHOCK WAVES　27　(3)　423-430　2017/05

DOI： 10.1007/s00193-016-0669-5 　

ISSN： 0938-1287

eISSN： 1432-2153
Underwater Expansion Wave Focusing by Reflecting at the Air Interface Peer-reviewed

K. Ohtani, T. Ogawa

SELECTED PAPERS FROM THE 31ST INTERNATIONAL CONGRESS ON HIGH-SPEED IMAGING AND PHOTONICS　10328　2017

DOI： 10.1117/12.2268514 　

ISSN： 0277-786X
Pulsed laser-induced liquid jet: evolution from shock/bubble interaction to neurosurgical application Peer-reviewed

A. Nakagawa, T. Kumabe, Y. Ogawa, T. Hirano, T. Kawaguchi, K. Ohtani, T. Nakano, C. Sato, M. Yamada, T. Washio, T. Arafune, T. Teppei, K. Atsushi, S. Satomi, K. Takayama, T. Tominaga

SHOCK WAVES　27　(1)　1-14　2017/01

DOI： 10.1007/s00193-016-0696-2 　

ISSN： 0938-1287

eISSN： 1432-2153
Highly Temporal Visualization of Propagation Process of Underwater Negative Streamer

Ryo Kumagai, Seiji Kanazawa, Atsuki Komiya, Kiyonobu Ohtani, Toshiro Kaneko, Tomoki Nakajima, Takehiko Sato

Proceedings of the 3rd Taiwan-Japan Workshop on Plasma Life Science and Technology (2016TJPL)　PO-02　2016/12/15
爆風による外傷性損傷：テロ対応の観点から Peer-reviewed

中川敦寛, 大谷清伸, 富田博秋, 久志本成樹, Rocco Armonda, 冨永悌二

安全工学　55　(6)　441-446　2016/12

DOI： 10.18943/safety.55.6_441 　
Turbulent jet interaction with a long rise-time pressure signature Peer-reviewed

Takahiro Ukai, Kiyonobu Ohtani, Shigeru Obayashi

APPLIED ACOUSTICS　114　179-190　2016/12

DOI： 10.1016/j.apacoust.2016.07.015 　

ISSN： 0003-682X

eISSN： 1872-910X
Expansion wave and cavitation bubble generation by underwater shock wave reflection from the interface Peer-reviewed

K. Ohtani, T. Ogawa

Mechanical Engineering Journal, JSME　3　(6)　16-00298-1-16-00298-7　2016
Shock Hugoniot and equations of states of water, castor oil, and aqueous solutions of sodium chloride, sucrose and gelatin Peer-reviewed

A. B. Gojani, K. Ohtani, K. Takayama, S. H. R. Hosseini

SHOCK WAVES　26　(1)　63-68　2016/01

DOI： 10.1007/s00193-009-0195-9 　

ISSN： 0938-1287

eISSN： 1432-2153
Role of Continuous Discharge Current for Secondary Streamer in Water Peer-reviewed

H. Fujita, S. Kanazawa, K. Ohtani, A. Komiya, T. Kaneko, T. Sato

International Journal of Plasma Environmental Science & Technology　10　(1)　16-19　2016
Study on Underwater Processing by CO2 Laser-Induced Bubble Column:(Consideration of Transmission Laser Energy Estimating Method) Peer-reviewed

OHTANI Kiyonobu, KOBAYASHI Toshio

JAPANESE JOURNAL OF MULTIPHASE FLOW　30　(1)　57-64　2016
Publisher: THE JAPANESE SOCIETY FOR MULTIPHASE FLOW
DOI： 10.3811/jjmf.30.57 　

ISSN： 0914-2843

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This paper reports consideration of the transmission laser energy estimating method for an efficient underwater processing with support form a CO2 laser-induced bubble column. To calculate the transmission laser energy through the laser induced bubble column in water, the experiment of pulsed CO2 laser-induced bubble column formation visualization and laser energy measurement though the CO2 laser-induced bubble column in water was performed. The process of the CO2 laser-induced bubble generation was observed by high-speed video camera. Pulsed 50W CO2 laser beam of 10.6 μm in wavelength was irradiated onto the water surface, and then bubble is generated near the water surface. With further transmission of laser beams through the growing the bubble, local vaporization was continued and the bubble length was elongated. The transmitted energy though the bubble column was estimated by time rate of bubble growth time and was corrected for absorption loss and reflectance loss, and compared with the measured transmitted energy by power meter.
Mechanism of Traumatic Brain Injury at Distant Locations After Exposure to Blast Waves: Preliminary Results from Animal and Phantom Experiments Peer-reviewed

Atsuhiro Nakagawa, Kiyonobu Ohtani, Keisuke Goda, Daisuke Kudo, Tatsuhiko Arafune, Toshikatsu Washio, Teiji Tominaga

INTRACRANIAL PRESSURE AND BRAIN MONITORING XV　122　3-7　2016

DOI： 10.1007/978-3-319-22533-3_1 　

ISSN： 0065-1419
Bow-shock instability induced by Helmholtz resonator-like feedback in slipstream Peer-reviewed

Naofumi Ohnishi, Yosuke Sato, Yuta Kikuchi, Kiyonobu Ohtani, Kanako Yasue

PHYSICS OF FLUIDS　27　(6)　066103-1-066103-16　2015/06

DOI： 10.1063/1.4922086 　

ISSN： 1070-6631

eISSN： 1089-7666
Validation of measurement accuracy for near-field pressure around supersonic projectiles in a ballistic range Peer-reviewed

Takahiro Ukai, Kiyonobu Ohtani, Shigeru Obayashi

MEASUREMENT　67　24-33　2015/05

DOI： 10.1016/j.measurement.2015.01.031 　

ISSN： 0263-2241

eISSN： 1873-412X
Application of PSP technique to near-field sonic boom measurements in a ballistic range Peer-reviewed

Daiju Numata, Keisuke Asai, Kiyonobu Ohtani

53rd AIAA Aerospace Sciences Meeting　2015
Publisher: American Institute of Aeronautics and Astronautics Inc, AIAA
DOI： 10.2514/6.2015-0024 　
Translational research for blast-induced traumatic brain injury: Injury mechanism to development of medical instruments. Peer-reviewed

Nakagawa A, Ohtani K, Arafune T, Washio T, Iwasaki M, Endo T, Ogawa Y, Kumabe T, Takayama K, Tominaga T

29th International Symposium on Shock Waves 2　889-891　2015
Micro-explosive-induced underwater shock wave propagation and reflection at the interface Peer-reviewed

Kiyonobu Ohtani, Toshihiro Ogawa

SCIENCE AND TECHNOLOGY OF ENERGETIC MATERIALS　76　(5-6)　139-143　2015

ISSN： 1347-9466
Attenuation of underwater explosion propagating through porous compressible foam Peer-reviewed

Science and technology of energetic materials　76　(5)　127-132　2015
Publisher: Japan Explosives Society
ISSN： 1347-9466
Using Classification Error Rate a New Image-Extraction Method of Debris Cloud at Hypervelocity Impact Peer-reviewed

沖義弘, 松本紀彦, 大谷清伸, 長谷川直, 槙原幹十朗

日本航空宇宙学会論文集　63　(4)　157-165　2015

ISSN： 1344-6460
水中正ストリーマの進展開始電圧に及ぼす放電パラメータの影響 Peer-reviewed

藤田英理, 金澤誠司, 大谷清伸, 小宮敦樹, 金子俊郎, 佐藤岳彦

静電気学会誌　39　(1)　21-26　2015
Initiation process and propagation mechanism of positive streamer discharge in water Peer-reviewed

Hidemasa Fujita, Seiji Kanazawa, Kiyonobu Ohtani, Atsuki Komiya, Toshiro Kaneko, Takehiko Sato

JOURNAL OF APPLIED PHYSICS　116　(21)　213301-1-213301-12　2014/12

DOI： 10.1063/1.4902862 　

ISSN： 0021-8979

eISSN： 1089-7550
Highly Temporal Visualization of Generation Process of Underwater Secondary Streamer From Developed Primary Streamer Peer-reviewed

Hidemasa Fujita, Seiji Kanazawa, Kiyonobu Ohtani, Atsuki Komiya, Toshiro Kaneko, Takehiko Sato

IEEE TRANSACTIONS ON PLASMA SCIENCE　42　(10)　2398-2399　2014/10

DOI： 10.1109/TPS.2014.2325937 　

ISSN： 0093-3813

eISSN： 1939-9375
Long rise-time pressure signature through jet turbulence in a laboratory-scale experiment

Takahiro Ukai, Yuta Saito, Ko Miyakoshi, Takayoshi Yamaguchi, Kiyonobu Ohtani, Shigeru Obayashi

29th Congress of the International Council of the Aeronautical Sciences, ICAS 2014　2014
Publisher: International Council of the Aeronautical Sciences
Sonic boom estimation using the multipole method for free-flight experiments

Yuta Saito, Takahiro Ukai, Ko Miyakoshi, Kiyonobu Ohtani, Shigeru Obayashi

52nd AIAA Aerospace Sciences Meeting - AIAA Science and Technology Forum and Exposition, SciTech 2014　2014
Publisher: American Institute of Aeronautics and Astronautics Inc.
爆風による外傷性脳損傷（blast-induced traumatic brain injury）．III 各種疾患 4. 外傷鈴木則宏、祖父江元、荒木信夫、宇川義一、川原信隆編集 Annual Review 2014神経 Peer-reviewed

中川敦寛, 大谷清伸, 合田圭介, Armonda R, 冨永悌二

中外医薬社　192-198　2014
Fast propagation of an underwater secondary streamer by the appearance of a continuous component in the discharge current Peer-reviewed

H. Fujita, S. Kanazawa, K. Ohtani, A. Komiya, T. Kaneko, T. Sato

EPL　105　(1)　15003-1-15003-5　2014/01

DOI： 10.1209/0295-5075/105/15003 　

ISSN： 0295-5075

eISSN： 1286-4854
Simultaneous visualization of surface and flow field for a projectile Peer-reviewed

Takahiro Ukai, Takamasa Kikuchi, Kiyonobu Ohtani, Shigeru Obayashi

JOURNAL OF VISUALIZATION　16　(4)　331-340　2013/11

DOI： 10.1007/s12650-013-0174-1 　

ISSN： 1343-8875

eISSN： 1875-8975
Spatiotemporal analysis of propagation mechanism of positive primary streamer in water Peer-reviewed

Hidemasa Fujita, Seiji Kanazawa, Kiyonobu Ohtani, Atsuki Komiya, Takehiko Sato

JOURNAL OF APPLIED PHYSICS　113　(11)　113304-1-113304-7　2013/03

DOI： 10.1063/1.4795765 　

ISSN： 0021-8979
Time‐resolved shock wave visualization using a pointdiffraction interferemeter Peer-reviewed

Kiyonobu Ohtani, Daiju Numata, Shigeru Obayashi

Proceedings of the 20th International Shock Interaction Symposium　2012/08/23
Effect of Shock Wave Reflection and Diffraction for Near-Field Pressure Measurement of Supersonic Projectile using Ballistic Range Peer-reviewed

Takahiro Ukai, Kiyonobu Ohtani, Shigeru Obayashi

Proceedings of the 20th International Shock Interaction Symposium　2012/08/22
Overpressure generation and repetition of collapsing microbubbles induced by shock wave reflection in a narrow gap Peer-reviewed

A. Abe, K. Ohtani, K. Takayama

SHOCK WAVES　21　(4)　331-339　2011/08

DOI： 10.1007/s00193-011-0315-1 　

ISSN： 0938-1287
Fundamental study on the terrain effects of mount-hiji on damages caused by the atomic bomb dropped in Hiroshima Peer-reviewed

Toshio Koizumi, Hiroyuku Takeishi, Kiyonobu Ohtani, Kazuyoshi Takayama

Journal of Wind Engineering　36　(3)　39-50　2011/07

DOI： 10.5359/jwe.36.39 　

ISSN： 1349-3507 1349-340X
Mechanisms of Primary Blast-Induced Traumatic Brain Injury: Insights from Shock-Wave Research Peer-reviewed

Atsuhiro Nakagawa, Geoffrey T. Manley, Alisa D. Gean, Kiyonobu Ohtani, Rocco Armonda, Akira Tsukamoto, Hiroaki Yamamoto, Kazuyoshi Takayama, Teiji Tominaga

JOURNAL OF NEUROTRAUMA　28　(6)　1101-1119　2011/06

DOI： 10.1089/neu.2010.1442 　

ISSN： 0897-7151
Visualization of weak shock waves emitted from a trombone Peer-reviewed

K. Takayama, K. Ohtani, T. Ogawa, T. Kikuchi, R. Takayama, T. Takahashi

The Journal of the Acoustical Society of America　129　(4)　2616-2616　2011
広島原爆被害に及ぼす比治山の地形効果に関する基礎的模擬実験 Peer-reviewed

小泉俊雄, 武石洋征, 大谷清伸, 高山和喜

日本風工学論文集　36　(3)　39-50　2011
blast-induced traumatic brain injury (bTBI)：multidisciplinary teamによる病態解明から機器開発まで． Peer-reviewed

中川敦寛, 荒船龍彦, 大谷清伸, 山本裕朗, 松永忠雄, 鷲尾利克, 塚本哲, 中野徹, 仲井正昭, 合田圭介, 小川欣一, 孫明宇, 隈部俊宏, 芳賀洋一, Bahram Jalali, 牛田多加志, 高山和喜, 西野精治, 新家光雄, 佐久間一郎, 冨永悌二

神経外傷　33　187-194　2010
Pressure Generation from Micro-Bubble Collapse at Shock Wave Loading Peer-reviewed

A. Abe, K. Ohtani, K. Takayama, S. Nishio, H. Miura, M. Takeda

Journal of Fluid Science and Technology　5　(2)　235-246　2010
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jfst.5.235 　

ISSN： 1880-5558

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This paper reports the result of a primary experimental and analytical study used to explore a reliable technology that is potentially applicable to the inactivation of micro-creatures contained in ship ballast water. A shock wave generated by the micro-explosion of a 10mg silver azide pellet in a 10mm wide parallel test section was used to interact with a bubble cloud consisting of bubbles with average diameter 10µm produced by a swirling flow type micro-bubble generator. Observations were carried out with a high-speed camera, IMACON200, and the corresponding rebound pressures of the collapsing bubbles were measured with a fiber optic probe pressure transducer that provides high spatial and temporal resolutions. We found that micro-bubbles collapse in several hundred nanoseconds after the shock exposure and the resulting peak pressure pulses that repeatedly occurred exceeded well over 200MPa measured at the 20mm distance from the explosion center. These continued for well over 20µs. The experimental pressure responses were explained by solving the one-dimensional bubble Rayleigh-Plesset equation. Such high peak pressures could be used effectively for the inactivation of micro-creatures contained in ship ballast water.
Application of Shock Pressures Generated by Collapsing Microbubbles to Inactivation Treatment of Marine Bacteria in Ship Ballast Water Peer-reviewed

Abe Akihisa, Ohtani Kiyonobu, Takayama Kazuyoshi, Mimura Haruo, Nishio Shigeru, Sou Akira, Biyu Wan

International Symposium on Marine Engineering (ISME) 2009　DT-1, No.16　2009/10
Experimental study of underwater rock drilling using a pulsed Ho:YAG laser-induced jets Peer-reviewed

K. Ohtani, D. Numata, K. Takayama, T. Kobayashi, K. Okatsu

SHOCK WAVES　19　(5)　403-412　2009/10

DOI： 10.1007/s00193-009-0221-y 　

ISSN： 0938-1287
Diffuse holographic interferometric observation of shock wave reflection from a skewed wedge Peer-reviewed

D. Numata, K. Ohtani, K. Takayama

SHOCK WAVES　19　(2)　103-112　2009/06

DOI： 10.1007/s00193-009-0204-z 　

ISSN： 0938-1287

eISSN： 1432-2153
Pressure generation from micro-bubble collapse at shock wave loading Peer-reviewed

Akihisa Abe, Kiyonobu Ohtani, Kazuyoshi Takayama, Shigeru Nishio, Haruo Mimura, Minoru Takeda

Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B　75　(752)　668-675　2009
Publisher: Japan Society of Mechanical Engineers
DOI： 10.1299/kikaib.75.752_668 　

ISSN： 0387-5016
Experimental study of shock wave and bubble generation by pulsed CO2 laser beam irradiation into muddy water Peer-reviewed

K. Ohtani, D. Numata, K. Takayama, T. Kobayashi, K. Okatsu

SHOCK WAVES, VOL 2, PROCEEDINGS　901-+　2009
衝撃波作用による微小気泡群の崩壊と衝撃圧生成 Peer-reviewed

阿部晃久, 大谷清伸, 高山和喜, 西尾茂, 三村治夫, 武田実

日本機械学会論文集（B編）　75　(752)　668-675　2009
HVI tests on CFRP laminates at low temperature Peer-reviewed

D. Numata, K. Ohtani, M. Anyoji, K. Takayama, K. Togami, M. Sun

INTERNATIONAL JOURNAL OF IMPACT ENGINEERING　35　(12)　1695-1701　2008/12

DOI： 10.1016/j.ijimpeng.2008.07.055 　

ISSN： 0734-743X
Experimental study of hypervelocity impacts at low temperatures Peer-reviewed

D. Numata, K. Ohtani, M. Anyoji, K. Takayama, M. Sun

SHOCK WAVES　18　(3)　169-183　2008/08

DOI： 10.1007/s00193-008-0156-8 　

ISSN： 0938-1287
Heat flux measurement over a cone in a shock tube flow Peer-reviewed

T. Kuribayashi, K. Ohtani, K. Takayama, V. Menezes, M. Sun, T. Saito

SHOCK WAVES　16　(4-5)　275-285　2007/05

DOI： 10.1007/s00193-006-0068-4 　

ISSN： 0938-1287
Effect of debris fragments on direct initiation of spherical detonation waves in stoichiometric oxygen/hydrogen mixtures Peer-reviewed

Makoto Komatsu, Kazuyoshi Takayama, Kiyonobu Ohtani, Tsutomu Saito

PROCEEDINGS OF THE COMBUSTION INSTITUTE　31　2437-2443　2007

DOI： 10.1016/j.proci.2006.08.111 　

ISSN： 1540-7489
A study of hypervelocity impact on cryogenic materials Peer-reviewed

K. Ohtani, D. Numata, T. Kikuchi, M. Sun, K. Takayama, K. Togami

INTERNATIONAL JOURNAL OF IMPACT ENGINEERING　33　(1-12)　555-565　2006/12

DOI： 10.1016/j.ijimpeng.2006.09.025 　

ISSN： 0734-743X
Hypervelocity impact phenomena at low temperatures using a cryostat Peer-reviewed

K. Ohtani, D. Numata, T. Kikuchi, M. Sun, K. Takayama

SPACE DEBRIS AND SPACE TRAFFIC MANAGEMENT SYMPOSIUM 2005　112　353-+　2006

ISSN： 0278-4017
Attenuation of shock waves propagating over arrayed baffle plates Peer-reviewed

F Ohtomo, K Ohtani, K Takayama

SHOCK WAVES　14　(5-6)　379-390　2005/12

DOI： 10.1007/s00193-005-0282-5 　

ISSN： 0938-1287
Axisymmetric shock wave interaction with a cone: a benchmark test Peer-reviewed

M Sun, T Saito, PA Jacobs, EV Timofeev, K Ohtani, K Takayama

SHOCK WAVES　14　(5-6)　313-331　2005/12

DOI： 10.1007/s00193-005-0258-5 　

ISSN： 0938-1287
Hypervelocity impact phenomena at low temperatures using a cryostat

K. Ohtani, D. Numata, T. Kikuchi, M. Sun, K. Takayama

International Astronautical Federation - 56th International Astronautical Congress 2005　4　2668-2677　2005
Applications of shock wave research to medicine Peer-reviewed

K Takayama, K Ohtani

Computational Methods and Experimental Measurements XII　41　653-661　2005

ISSN： 1746-4064
Interaction of a Shock Wave with a Gas Bubble in Highly Viscous Liquid

Ohtani Kiyonobu, Yamamoto Hiroaki, Saito Tsutomu, Takayama Kazuyoshi

The proceedings of the JSME annual meeting　2004　37-38　2004
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmemecjo.2004.2.0_37 　

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This paper reports the results of experimental results of shock wave/ bubble interaction in a highly viscous liquid. In the medical applications of the shock waves, it is necessary to consider the viscous effect of water. The magma fragmentation is considered to be one of the major mechanisms of the explosive-type volcano eruptions. The dynamic motion of magma should be experimentally investigated from the view point of shock wave dynamics. Silver azide pellet was exploded in silicone oil and starch syrup with various viscosity was visualized by shadowgraph using high speed video camera.
Dynamic characteristics of a check valve for drain pumps

Hiromu Sugiyama, Kiyonobu Ohtani, Yuji Sasaki, Hiroyuki Musha, Kazuhide Mizobata, Takashi Ohishi, Toshio Miwa

Proceedings of the ASME/JSME Joint Fluids Engineering Conference　2　2851-2856　2003
Publisher: American Society of Mechanical Engineers
DOI： 10.1115/fedsm2003-45256 　
Dynamic characteristics of a check valve for drain pumps Peer-reviewed

Kazuhide Mizobata, Hiromu Sugiyama, Kiyonobu Ohtani, Takashi Ohishi, Yuji Sasaki, Hiroyuki Musha, Toshio Miwa

Nippon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B　68　(672)　2225-2231　2002
Publisher: Japan Society of Mechanical Engineers
DOI： 10.1299/kikaib.68.2225 　

ISSN： 0387-5016
Large-amplitude shock wave propagation and bubble collapse in a water containing gas bubbles Peer-reviewed

Kiyonobu Ohtani, Hiromu Sugiyama, Kazuhide Mizobata

Nippon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B　68　(670)　1646-1652　2002
Publisher: Japan Society of Mechanical Engineers
DOI： 10.1299/kikaib.68.1646 　

ISSN： 0387-5016
排水ポンプ用逆流防止弁の動特性 Peer-reviewed

溝端一秀, 杉山弘, 大谷清伸, 大石聖史, 佐々木悠二, 武者裕之, 三輪俊夫

日本機械学会論文集（B編）　68　(672)　2225-2231　2002
気泡を含む液体中を伝播する強い衝撃波と気泡崩壊 Peer-reviewed

大谷清伸, 杉山弘, 溝端一秀

日本機械学会論文集（B編）　68　(670)　1646-1652　2002

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Misc. 68

Quantitative Density Measurement of Unsteady Flow Field around Re-Entry Capsule Model

井川将大, 高坂菜央, 猪狩優斗, 山岸雅人, 太田匡則, 稲毛達朗, 川野理人, 大谷清伸, 永井大樹

衝撃波シンポジウム講演論文集(CD-ROM)　2023　2024
Simultaneous Measurement of Three-Dimensional Density Field around Hayabusa Capsule Model and the Angle of Attack in a ballistic range

山岸雅人, 高坂菜央, 廣瀬裕介, 稲毛達朗, 宇田川真介, 太田匡則, 滝川侑弥, 大谷清伸, 永井大樹

衝撃波シンポジウム講演論文集(CD-ROM)　2023　2024
Density measurement around a Reentry capsule in Ballistic range

山岸雅人, 廣瀬裕介, 太田匡則, 細野陽太, 大谷清伸, 永井大樹

衝撃波シンポジウム講演論文集(CD-ROM)　2022　2023
High-accurate density measurement around the Re-entry capsule model

片桐優太郎, 高坂菜央, 楢山仁, 山岸雅人, 廣瀬祐介, 太田匡則, 野村将之, 藤田昂志, 大谷清伸, 永井大樹

衝撃波シンポジウム講演論文集(CD-ROM)　2021　2022
Qualitative Density Measurement of Wake Region Behind Re-Entry Capsule

太田匡則, 永井大樹, 廣瀬裕介, 稲毛達朗, 大谷清伸

東北大学流体科学研究所共同利用・共同研究拠点流体科学国際研究教育拠点活動報告書(CD-ROM)　2020　2021
Qualitative density measurement of wake region behind re-entry capsule

太田匡則, 永井大樹, 廣瀬裕介, 稲毛達朗, 大谷清伸

東北大学流体科学研究所共同利用・共同研究拠点流体科学国際研究教育拠点活動報告書(CD-ROM)　2021　2021
The Quantitative Density Measurement of Unsteady Flow around a Projectile

太田匡則, 永井大樹, 廣瀬裕介, 稲毛達朗, 大谷清伸

東北大学流体科学研究所共同利用・共同研究拠点流体科学国際研究教育拠点活動報告書(CD-ROM)　2019　2021
Pressure change due to time scale between the pressure waveforms and the turbulent field

中川穂南, 鵜飼孝博, 大谷清伸

飛行機シンポジウム講演集(CD-ROM)　59th　2021
Effects of the Turbulence Interaction on the Rise Time of a Sonic Boom Pressure Signature

鵜飼孝博, 大谷清伸, 中川穂南

東北大学流体科学研究所共同利用・共同研究拠点流体科学国際研究教育拠点活動報告書(CD-ROM)　2020　2021
Effects of the Turbulence Interaction on the Rise Time of a Sonic Boom Pressure Signature

鵜飼孝博, 大谷清伸, 中川穂南, 焼野藍子

東北大学流体科学研究所共同利用・共同研究拠点流体科学国際研究教育拠点活動報告書　2019　2021
Flow Fields and Flight Characteristics of Transonic Free-flight Next-Generation Reentry Capsule

四方一真, 田中直樹, 高橋幸一, 小川俊広, 大谷清伸, 藤田昂志, 永井大樹, 山田和彦

流体力学講演会/航空宇宙数値シミュレーション技術シンポジウム講演集(CD-ROM)　53rd-39th　2021
Dispersion of debris during under water application of pulsed water jet device

影山宗祐, 中川敦寛, 中川敦寛, 川口奉洋, 大谷清伸, 大沢伸一郎, 遠藤俊毅, 冨永悌二

日本生体医工学会大会プログラム・抄録集(Web)　60th　2021
弾道飛行装置実験により自由飛行するカプセルの遷音速域における後流の時空間構造の特徴抽出

桐谷英樹, 永井大樹, 藤田昂志, 大谷清伸

2019年度衝撃波シンポジウム講演論文集　2020/03
The Quantitative Density Measurement of Unsteady Flow around a Projectile

太田匡則, 永井大樹, 栗原健, 稲毛達朗, 大谷清伸

東北大学流体科学研究所共同利用・共同研究拠点流体科学国際研究教育拠点活動報告書　2018　2020
Transonic Flow Field Analysis of a Free Flight Capsule using Ballistic Range

Hideki Kiritani, Naoki Tanaka, Kiyonobu Ohtani, Koji Fujita, Hiroki Nagai

AIAA Scitech 2020 Forum　2020/01

DOI： 10.2514/6.2020-1990 　
災害(テロ災害・検証) 爆風損傷臨床、診療体制、課題

中川敦寛, ロッコ・アーモンダ, 大谷清伸, ガイ・ローゼンタール, 刈部博, 冨田博秋, 佐久間篤, 八木橋真央, ジェフリー・マンレー, 久志本成樹, 冨永悌二

Neurosurgical Emergency　23　(3)　279-279　2019/02
Publisher: (NPO)日本脳神経外科救急学会
ISSN： 1342-6214
遷音速域における自由飛行カプセルの後流解析

桐谷英樹, 永田貴之, 永井大樹, 大谷清伸, 小川俊広

衝撃波シンポジウム講演論文集(CD-ROM)　2018　ROMBUNNO.1A3‐2　2019
Schlieren visualization of transonic and supersonic flow over a sphere at reynolds number between 10³and 10⁵through free-flight tests Peer-reviewed

Takayuki Nagata, Akito Noguchi, Taku Nonomura, Toshihiro Ogawa, Kiyonobu Ohtani, Kesuke Asai

AIAA Scitech 2019 Forum　2019

DOI： 10.2514/6.2019-2156 　
自由落下する小球と垂直衝撃波の干渉のシュリーレン可視化および球の抵抗係数の推定

永田貴之, 野々村拓, 大谷清伸, 浅井圭介

衝撃波シンポジウム講演論文集(CD-ROM)　2018　ROMBUNNO.1A1‐3　2019
Numerical study on micro-explosive induced shock wave propagation in a closed space.

Ohtani K, T. Ogawa, A. Abe, A. Nakagawa

2019
爆傷と銃創臨床、診療体制

中川敦寛, Armonda Rocco, Rosenthal Guy, 大谷清伸, 冨田博秋, 佐久間篤, 八木橋真央, Manley Geoffrey, 久志本成樹, 冨永悌二

Japanese Journal of Acute Care Surgery　8　(1)　44-44　2018/09
Publisher: 日本Acute Care Surgery学会
衝撃波の医療応用:最近の動向もふまえて

中川敦寛, 遠藤俊毅, 遠藤英徳, 大沢伸一郎, 冨永悌二, 中西史, 横沢友樹, 山下慎一, 飯久保正弘, 佐藤由加, 佐久間篤, 八木橋真央, 近野敦, 辻田哲平, 大谷清伸

衝撃波シンポジウム講演論文集(CD-ROM)　2017　2018
バリスティックレンジによるレイノルズ数10⁴オーダーの遷・超音速球周り流れのシュリーレン可視化

永田貴之, 野口暁人, 小川俊広, 野々村拓, 大谷清伸, 浅井圭介

衝撃波シンポジウム講演論文集(CD-ROM)　2017　ROMBUNNO.3C3‐2　2018
閉空間内微小爆薬起爆による水中衝撃波発生挙動

大谷清伸, 中川敦寛, 中川桂一, 小川俊広

平成28年度衝撃波シンポジウム講演論文集　2017
Drag Measurement of a Sphere Model in Supersonic Free Flight Using the Ballistic Range

川上遼兼, 渡邊正人, 中島辰馬, 菊地亮太, 大谷清伸, 大林茂

年会講演会講演集　47　6p　2016/04/14
Publisher: 日本航空宇宙学会
167 Visualization of propagation process of negative discharge in water

KUMAGAI Ryo, KANAZAWA Seiji, OHTANI Kiyonobu, KOMIYA Atsuki, KANEKO Toshiro, NAKAJIMA Tomoki, SATO Takehiko

2016　(51)　131-132　2016
Publisher: The Japan Society of Mechanical Engineers
生体模擬物質モデルを用いた衝撃波細胞干渉挙動模擬

大谷清伸, 中川敦寛, 中川桂一

平成27年度衝撃波シンポジウム　2016
生体模擬物質中の衝撃波伝播挙動

大谷清伸, 中川敦寛, 中川桂一

火薬学会2015年度秋季研究発表会　59-62　2015/12
OS1507-368 Study on Low Velocity Soft-body Projectile Impact on a Thin Plate

OHTANI Kiyonobu, OGAWA Toshihiro

2015　"OS1507-368-1"-"OS1507-368-3"　2015/11/21
Publisher: The Japan Society of Mechanical Engineers

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This paper reports the preliminarily experimental results of low velocity soft-body projectile made of gelatin solution impact test on a thin plate at impact speed of about 120 m/s. An experimental investigation of low velocity impact was performed by using a ballistic range at Institute of Fluid Science, Tohoku University. The process of impact and shock wave propagation phenomena was visualized by shadowgraph method and recorded by a high-speed video camera.
1004 Unsteady Pressure Field Measurement in Ballistic-range Experiments by Using Ultrafast-response PSP

NUMATA Daiju

Fluids engineering conference ...　2015　"1004-1"-"1004-2"　2015/11/07
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-0251

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In this study, we conducted preliminary experiments to visualize unsteady pressure field caused by shock waves from free-flight projectiles which is launched by ballistic range. For this purpose, we visualized shock-wave propagation on sample plate by using ultrafast-response PSP and high-sensitivity high-speed video camera. Visualization results were well agreement qualitatively compared with past results.
OS5-2 Expansion Wave and Bubble Generation by Underwater Shock Wave Reflection from the Interface(Bubble and Material imaging,OS5 High-speed imaging and photonics,MEASUREMENT METHODS)

Ohtani Kiyonobu, Ogawa Toshihiro

Abstracts of ATEM : International Conference on Advanced Technology in Experimental Mechanics : Asian Conference on Experimental Mechanics　2015　(14)　63-63　2015/10/04
Publisher: The Japan Society of Mechanical Engineers
模擬モデルを用いた爆風による外傷性脳損傷機序解明に関する数値模擬

大谷清伸, 中川敦寛, 沼田大樹

M&M2015 材料力学カンファレンスプロシーディング　369-371　2015
1305 Highly temporal analysis of underwater streamers with a streak camera

FUJITA Hidemasa, KANAZAWA Seiji, OHTANI Kiyonobu, KOMIYA Atsuki, KANEKO Toshiro, SATO Takehiko

Fluids engineering conference ...　2014　"1305-1"-"1305-2"　2014/10/25
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-0251

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The highly temporal streak imaging of an underwater discharge revealed that the primary streamer propagation was intermittent though the propagation had been considered continuous from our previous study. In addition, the intermittent luminescence pattern was synchronized with the pattern of discharge pulsed currents. The primary streamer in ultrapure water was generated by the application of a single-shot pulsed positive high voltage with a duration of 10 μs to a needle-wire electrode system with the tip radius of 40 μm and with the gap distance of 6 mm.
OS1718 Visualization of shock wave propagation by hypervelocity impact

OHTANI Kiyonobu, OGAWA Toshihiro

2014　"OS1718-1"-"OS1718-3"　2014/07/19
Publisher: The Japan Society of Mechanical Engineers

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This paper reports the preliminarily experimental results of shock wave propagation visualization by hypervelocity impact. An experimental investigation of hypervelocity impact was performed by using a ballistic range at Institute of Fluid Science, Tohoku University. The process of shock wave propagation by hypervelocity impact was visualized by shadowgraph method and recorded by high-speed video camera.
Shock-turbulence interaction in high and low humidity field

45　7p　2014/04/10
Publisher: 日本航空宇宙学会
113 Experimental study on Tsunami mitigation effect in rectangular horizontal channel

OHTANI Kiyonobu, SAITO Tsutomu

2014　(49)　27-28　2014
Publisher: The Japan Society of Mechanical Engineers

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This paper reports a preliminary experimental result of tsunami interaction phenomena with cylinder models for tsunami mitigation effect in rectangular horizontal channel. The process of simulated tsunami wave interaction with simple cylinder models in rectangular channel was observed by a digital camera. The velocity of simulated tsunami wave after interacting with cylinder models was measured a laser interrupting signal by passage through the wave.
模擬モデルを用いた爆風による外傷性脳損機序解明研究

大谷清伸, 中川敦寛, 沼田大樹, 合田圭介, 荒船龍彦, 鷲尾利克, 古川宗, Mark Richardson, 早瀬敏幸

日本機械学会第26回バイオエンジニアリング講演　33-34　2014
爆風による外傷性脳損傷機序解明のための模擬物質中の衝撃波伝播挙動

大谷清伸, 中川敦寛, 沼田大樹, 合田圭介, 荒船龍彦, 鷲尾利克

平成25年度衝撃波シンポジウム　152-154　2014
Ground Experiment of Supersonic Biplane Theory

OBAYASHI Shigeru, YAMASHITA Hiroshi, OHTANI Kiyonobu, KIKUCHI Takamasa, UKAI Takahiro

Journal of the Japan Society for Aeronautical and Space Sciences　61　(4)　123-128　2013/04/05
Publisher: The Japan Society for Aeronautical and Space Sciences
ISSN： 0021-4663
143 Process of Primary Streamer Propagation in Water

FUJITA Hidemasa, KANAZAWA Seiji, OHTANI Kiyonobu, Komiya Atsuki, SATO Takehiko

2013　(48)　88-89　2013/03/15
Publisher: The Japan Society of Mechanical Engineers
Cavitation bubble and high-pressure generation phenomena by underwater expansion wave focusing

33　(1)　219-222　2013
Publisher: 可視化情報学会
ISSN： 0916-4731
爆風による外傷性脳損傷機序解明に関する研究

大谷清伸, 中川敦寛, 合田圭介, 荒船龍彦, 鷲尾利克, 早瀬敏幸

平成24年度衝撃波シンポジウム　303-304　2013
爆風による外傷性脳損傷機序解明のための模擬モデル実験

大谷清伸, 中川敦寛, 沼田大樹, 合田圭介, 荒船龍彦, 鷲尾利克, 古川宗, Mark Richardson, 早瀬敏幸

高速度イメージングとフォトニクスに関する総合シンポジウム　22　2013
爆風による外傷性脳損傷機序解明に関する研究

大谷清伸, 中川敦寛, 合田圭介, 荒船龍彦, 鷲尾利克, 早瀬敏幸

平成24年度衝撃波シンポジウム講演論文集　304-305　2013
Streamer Propagation Process of Plasma in Water

FUJITA Hidemasa, SATO Takehiko, KANAZAWA Seiji, OHTANI Kiyonobu, KOMIYA Atsuki

2012　(107)　21-24　2012/12/10
S055012 Visualization of a streamer propagation process in water

SATO Takehiko, FUJITA Hidemasa, KANAZAWA Seiji, OHTANI Kiyonobu, KOMIYA Atsuki

Mechanical Engineering Congress, Japan　2012　"S055012-1"-"S055012-2"　2012/09/09
Publisher: The Japan Society of Mechanical Engineers

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A series of photographs for a streamer propagation process in water was successfully observed using a nano-pulse discharge system, an ultra high speed camera system with a microscope lens and a phase shift type Mach-Zehnder interferometer. After the initiation process of 600 ns - 800 ns from the applying voltage of 16 kV_<0p> - 17.5 kV_<0p>, a primary streamer occurred. It accompanied with a shock wave and the period of the propagation was several hundred ns. The propagation velocity of the primary streamer was around 1.5 km/s.
309 Processes of Streamer Propagation in Water

Fujita Hidemasa, Kanazawa Seiji, Otani Kiyonobu, Komiya Atsuki, Sato Takehiko

Symposium on Environmental Engineering　2012　(22)　209-210　2012/07/03
Publisher: The Japan Society of Mechanical Engineers

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A continuous photograph of a streamer propagation process in water was successfully observed using a nano-pulse discharge system, an ultra high speed camera system with a microscope lens and a phase shift type Mach-Zehnder interferometer. After the initiation process of 600 ns - 800 ns from the applying voltage of 16 kV0p-17.5 kV0p, a primary streamer was occurred. It accompanied with a shock wave and the period of the propagation was several hundred ns. The propagation velocity of the primary streamer was around 1.5 km/s.
132 Underwater Expansion Wave and Bubble Generation Phenomena Near the Water Surface

OHTANI Kiyonobu, OGAWA Toshihiro, Obayashi Shigeru

2012　(47)　70-71　2012/03/13
Publisher: The Japan Society of Mechanical Engineers

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This paper reports a preliminary experimental result of the expansion wave and cavitation bubble generation near the water surface. Underwater spherical shock wave generated by detonating of micro explosive of a 10 mg silver azide (AgN_3)pellets propagated and reflected from the water surface. The reflected wave is an expansion wave. The process of expansion wave and cavitation bubble generation near the water surface were observed by shadowgraph method and recorded by a high-speed camera. The pressure distribution near the water surface was measured by a PVDF needle hydrophone.
生体模擬物質中を伝播する衝撃波現象

大谷清伸, 中川敦寛, 早瀬敏幸, 荒船龍彦, 鷲尾利克, 合田圭介

平成23年度衝撃波シンポジウム講演論文集　125-126　2012
小型回転楕円体を用いた微小爆薬起爆水中衝撃波収束現象

大谷清伸, 大谷清伸, 山本裕朗, 山本裕朗, 高山和喜, 下川宏明

衝撃波シンポジウム講演論文集　2010　2011
Blast Wave/衝撃波の頭蓋内伝播経路・動態の解析

中川敦寛, 高山和喜, 大谷清伸, 山本裕朗, GEAN Alisa, ARMONDA Rocco, 冨永悌二

東北大学流体科学研究所共同利用・共同研究拠点流体科学研究拠点活動報告書　2010　2011
Biological and Mechanical Profile of Bench Top Blast Wave Traumatic Brain Injury Model in Rat

Atsuhiro Nakagawa, Kiyonobu Ohtani, Hiroaki Yamamoto, Kazuyoshi Takayama, Teiji Tominaga

JOURNAL OF NEUROSURGERY　113　(2)　A415-A415　2010/08

ISSN： 0022-3085
Blast wave injury:multidisciplinary teamによる損傷機序解明の取り組み

中川敦寛, 大谷清伸, MANLEY Geoffrey, ARMONDA Rocco, GEAN Alisa, 山本裕朗, 高山和喜, 冨永悌二

日本脳神経外傷学会プログラム・抄録集　33rd　2010
球の砂突入に関する研究

山本裕朗, 大谷清伸, 早坂庄吉, 小川俊宏, 高山和喜

衝撃波シンポジウム講演論文集　2009　2010
Multidisciplinary research platform for shock wave (blast wave) and traumatic brain injury : Injury mechanism to development of new technology and systems

Atsuhiro Nakagawa, Tatsuhiko Arafune, Kiyonobu Ohtani, Hiroaki Yamamoto, Tadao Matsunaga, Toshikatsu Washio, Akira Tsukamoto, Toru Nakano, Masaaki Nakai, Keisuke Goda, Yoshikazu Ogawa, Sun Myngu, Toshihiro Kumabe, Yoichi Haga, Bahran Jalali, Takashi Ushida, Kazuyoshi Takayama, Seiji Nishino, Mitsuo Niinomi, Ichiro Sakuma, Teiji Tominaga

Neurotraumatology　33　(2)　187-194　2010

ISSN： 0389-5610
各種液体の状態方程式の計測

山本裕朗, 大谷清伸, 下川宏明, 高山和喜

衝撃波シンポジウム講演論文集　2008　2009
414 Study on cavitation and shock waves phenomena in liquid argon using an ultrasound transducer

Ohtani Kiyonobu, Numata Daijyu, Sun Mingyu, Takayama Kazuyoshi

Fluids engineering conference ...　2005　56-56　2005/10/28
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-2882
極低温高速衝突現象の数値シミュレーション

大谷清伸, 孫明宇, 沼田大樹

宇宙科学シンポジウム　5　581-584　2005/01/06
Publisher: 宇宙科学研究所
Experimental Study of Hypervelocity Impact Phenomena at Low Temperatures using a Cryostat

Ohtani Kiyonobu, Numata Daiju, Sun Mingyu, Takayama Kazuki

Fluids engineering conference ...　2004　132-132　2004/11/24
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-2882
A Study of Shock Wave Propagation Phenomena in Liquids Containing Gas Bubbles

OGASAWARA Hisatoshi, SUGIYAMA Hiromu, MIZOBATA Kazuhide, OHTANI Kiyonobu, YAMASHITA Akihiko

2003　(43)　56-57　2003/09/28
Publisher: The Japan Society of Mechanical Engineers
Study on Thrust of Jet from Nozzle Injecting Liquid Nitrogen

AONO Ichiro, HANAOKA Yutaka, OHTANI Kiyonobu

2003　(43)　62-63　2003/09/28
Publisher: The Japan Society of Mechanical Engineers
A Study of Large-Amplitude Shock Wave Phenomena in Air-Bubble/Water Mixtures

OHTANI Kiyonobu, SUGIYAMA Hiromu, MIZOBATA Kazuhide, OGASAWARA Hisatoshi

2002　(42)　50-51　2002/10/05
Publisher: The Japan Society of Mechanical Engineers

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The large-amplitude shock wave propagation phenomena in air-bubbles/water mixtures were investigated using a two-phase shock tube. Effect of incident shock wave strength on shock wave pressure characteristics in mixtures and the precursor of shock wave are analyzed. It was found that the large-amplitude shock waves have high-frequency oscillation components and the precursor.
507 Dynamic characteristics of a check valve for drain pumps

SASAKI Yuji, SUGIYAMA Hiromu, MIZOBATA Kazuhide, OHTANI Kiyonobu, OHISHI Takashi, MIWA Toshio, MUSHA Hiroyuki, OHKAWA Hironari

2001　(41)　160-161　2001/09/25
Publisher: The Japan Society of Mechanical Engineers

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We investigated experimentally the dynamic characteristics of a check valve used in drainages. The function of the check valve is to check the reverse flow in the drain pipes when the drain pumps accidentally stop. When the check valve closes suddenly, large impact force arises on the drain pipes and check valves, and then water column separation occurs near the check valves and water-hammer phenomenon occurs in the drain pipes. To find the methods for reducing impact forces, we investigated the flow phenomena around the check valve; impact acceleration of check valve and downstream tank, pressure variation and movement of the check valve.
521 A Study of Large-amplitude Shock Wave Propagation in Liquids Containing Gas Bubbles

OHTANI Kiyonobu, SUGIYAMA Hiromu, MIZOBATA Kazuhide, SASAKI Yuji

2001　(41)　188-189　2001/09/25
Publisher: The Japan Society of Mechanical Engineers

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The large-amplitude shock wave propagation phenomena in air-bubbles/ water mixtures were investigated using a two-phase shock tube. Effect of incident shock wave strength on shock wave pressure characteristics in mixtures and the precursor of shock wave are analyzed. Behavior of the bubbles collapsing behind large-amplitude shock wave are also detected by high-speed photography. It was found that the large-amplitude shock waves have high-frequency oscillation components and the precursor.
316 Dynamic characteristic of a check valve for drain pumps

OHISHI Takashi, SUGIYAMA Hiromu, MIZOBATA Kazuhide, OHTANI Kiyonobu, SASAKI Yuji, MUSYA Hiroyuki, MIWA Toshio

2000　(40)　126-127　2000/09/25
Publisher: The Japan Society of Mechanical Engineers

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Check valves are mainly used in drainage systems of riversides. Their function is to check the reverse flow of water in the drain pipes. When check valves close, large shock force arises on the drain pipes and check valves, and at that time, water column separation and water-hammer phenomenon occurs near the check valves. As the result of these phenomena, the facilities are damaged. In order to investigate the impact force when the check valve suddenly closes, the impact pressure and impact acceleration measurements are made, and the flow near the check valve are visualized by a high speed video camera.
Dynamic characteristics of a check valve for drain pumps

SASAKI Yuji, SUGIYAMA Hiromu, MIZOBATA Kazuhide, OHTANI Kiyonobu, OHISHI Masashi, MUSHA Hiroyuki, MIWA Toshio

Fluids engineering conference ...　2000　233-233　2000/09/08
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-2882
Shock Wave Propagation in Liquids Containing Gas Bubble

OHTANI Kiyonobu, SUGIYAMA Hiromu, MIZOBATA Kazuhide, OHISHI Takashi, SASAKI Yuji

Fluids engineering conference ...　2000　132-132　2000/09/08
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-2882
気泡を含む液体中を伝播する衝撃波現象

大谷清伸

平成11年度衝撃はシンポジウム講演論文集　205-208　2000

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Presentations 3

Numerical study on micro-explosive induced shock wave propagation in a closed space International-presentation

K. Ohtani, T. Ogawa, A. Abe, A. Nakagawa

32nd International Symposium on Shock Waves (ISSW32)　2019/07/15
弾道飛行装置を用いたリング形状および板翼模型自由飛行実験

大谷清伸, 内海宏輝, 小川俊広, 小川秀朗, 大林茂

平成30年度航空宇宙空力シンポジウム　2019/01/25
Schlieren visualization of transonic and supersonic flow over a sphere at Reynolds number between 10^3 and 10^5 through free-flight tests International-presentation

T. Nagata, A. Noguchi, T. Nonomura, T. Ogawa, K. Ohtani, Keisuke Asai

AIAA Science and Technology Forum and Exposition 2019　2019/01/07

Industrial Property Rights 6

レーザビームを用いた物体加工方法および加工装置

小林俊雄, 中村雅洋, 大谷清伸

Property Type: Patent
レーザビームを用いた物体加工方法及び加工装置

Property Type: Patent
METHOD OF PROCESSING ROCK WITH LASER AND APPARATUS FOR SAME

Toshio Kobayashi, Kazuyoshi Takayama, Kiyonobu Ohtani, Satoru Umezu

Property Type: Patent
被処理水の殺菌方法及びその装置

阿部晃久, 高山和喜, 大谷清伸

Property Type: Patent
レーザを用いた岩石の加工方法及びその装置

小林俊雄, 高山和喜, 大谷清伸, 梅津覚

Property Type: Patent
レーザを用いた岩石の加工方法及びその装置

小林俊雄, 高山和喜, 大谷清伸, 梅津覚

特許第4270577号

Property Type: Patent

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Research Projects 31

爆風被害予防のための衝撃波影響評価と新たな爆風圧スケール則導出

大谷清伸, 沼田大樹

Offer Organization: 日本学術振興会

System: 科学研究費助成事業

Category: 基盤研究(C)

Institution: 東北大学

2024/04 - 2027/03
爆風損傷の初期診療におけるトリアージ法に関する基礎研究

中川敦寛, 大谷清伸, 大沢伸一郎, 園部真也, 辻田哲平, 近野敦, 佐瀬一弥, 下田由輝

Offer Organization: 日本学術振興会

System: 科学研究費助成事業基盤研究(B)

Category: 基盤研究(B)

Institution: 東北大学

2023/04 - 2026/03
硬い線維化腫瘍破砕のための超音波印加パルスジェットを用いた手術機器開発

川口奉洋, 中川敦寛, 吉川彰, 荒船龍彦, 大橋雄二, 金森政之, 大谷清伸

Offer Organization: 日本学術振興会

System: 科学研究費助成事業

Category: 基盤研究(C)

Institution: 東北大学

2022/04 - 2025/03

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高圧水流を利用した液体ジェットは、熱・粉塵の発生がなく、石や金属などの加工に用いられる切削技術である。本技術を医療に転用され血管温存下に臓器切開・破砕可能という特徴を有している。我々は、これを微小パルス流として発生する技術を2001年に開発した。神経・血管温存下の腫瘍破砕が可能とするパルスジェットメスの高い組織選択性を利用し、これまでに、神経膠腫や下垂体腺腫に対する摘出術において、摘出率の向上と出血量の減少を報告し、安全性と有効性を示してきた。しかし、線維化した硬い腫瘍に対しては有効な破砕が得られなかった。これに対し、射出される液滴径を減じることで、腫瘍内の線維成分の隙間に射出液滴が進入できるという仮説を立て、射出されるジェット流に超音波を印加し液滴を微粒化することで、組織内浸透性と局所破砕能向上を企図するものである。本年度の研究期間内に超音波振動素子を作成し、射出するジェット液滴を微粒化させることを企図。振動素子の形状や大きさなどを選択し、最適な射出条件を検討した。次年度以降、本条件をもとに模擬モデルを用いた実験に移行する。超音波印加による射出ジェット流の微粒化の知見は従来の手術機器ではなし得なかった線維化癒着病変の最大限摘出と機能温存を企図する点で学術的独自性と創造性をもつ。これは、硬い頭蓋内腫瘍の破砕のみにとどまらず、他科手術時の臓器癒着病変の安全な剥離、薬液の皮下浸潤投与技術の向上など、ヘルスケアや基礎研究まで広い波及効果を見込むものである。
音響インピーダンスを考慮した固気液混相多層媒体干渉を用いる新規衝撃波低減手法開発

大谷清伸

Offer Organization: 日本学術振興会

System: 科学研究費助成事業基盤研究(C)

Category: 基盤研究(C)

Institution: 東北大学

2021/04 - 2024/03

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本研究では、爆発等に伴う衝撃波圧力被害からの人や建築物の防御等に関連して、医学上、工学上重要な研究課題である衝撃波圧力の低減について、音響インピーダンスを考慮した固体、液体、気体の混相の多層媒体との干渉による新たな衝撃波圧力低減方法の確立を目的としている。この目的のため、初年度は固液粒子群、網状媒体との衝撃波干渉を行い、衝撃波低減に効果的な干渉の方法、干渉対象物を明らかにするための実験的な検討を行った。微小爆薬の起爆によって発生させた衝撃波を水液滴群、および重ねて多層にした網媒体と干渉させて、衝撃波干渉挙動を高時間・高空間分解能を有する光学可視化計測および圧力計測の同時計測によって明らかにした。固液それぞれの粒子群との干渉により、衝撃波のピーク過剰圧と衝撃波伝播速度が低減することが示された。そのうち、起爆後早い段階における粒子群との干渉で、衝撃波威力の低減がより効果的であることがわかった。特に水液滴群の場合には、起爆点に近い領域で水液滴が大きく変形、微粒化し抵抗が増すこと、高温の爆発生成ガスと干渉するために熱移動が大きくなり、これらの要因が衝撃波圧力低減に寄与していることが示唆される結果となった。多層網媒体との干渉では、網のメッシュ数が大きく、枚数をより多く重ねることでより効果的に衝撃波威力が低減すること、重ねる網間に一部空間を設けることで、干渉する多層網媒体からの反射衝撃波を低減することが示される結果が得られた。また、固液粒子群干渉による衝撃波低減効果に関する実験結果との比較検証として、粒子群干渉による衝撃波挙動を汎用数値解析ソフトウェアANSYS AUTODYNを用いて数値解析を行うための解析モデルの検討を行い、次年度以降の数値解析による検証の準備が整った。
複雑閉鎖空間中の爆風による生体内衝撃波伝播防止のための衝撃波工学・医学的検討

中川敦寛, 大沢伸一郎, 大谷清伸

Offer Organization: 日本学術振興会

System: 科学研究費助成事業挑戦的研究(萌芽)

Category: 挑戦的研究(萌芽)

Institution: 東北大学

2020/07/30 - 2023/03/31

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爆風脳損傷は、衝撃波を先行、かつ主成分とする爆風による脳損傷で、目に見えない外力によるため、機序、予防については解明されていない点が多い。東北大学学際衝撃波研究拠点は1970年以降世界的に拠点として衝撃波の医療応用はもちろん、さまざまな領域で衝撃波の学際研究を推進してきた。本研究の目的は、第一に閉鎖空間内で爆風損傷の先行、かつ主要成分を占める衝撃波の体内伝播動態を明らかにすること、第二に衝撃波による外傷性脳損傷を防止する技術開発に向け基礎的知見を得ることである。具体的には閉鎖空間内の反射・干渉により生体内に伝播する衝撃波を空間構造と材質で損傷閾値以下に減衰することに関して非臨床（動物実験）概念実証を確立する。本研究では、衝撃波工学の観点から模擬モデル実験と動物実験を行う。 2年目の本年は、昨年度東北大学流体科学研究所で実施してきた模擬モデル実験（単純閉鎖空間内の衝撃波伝播動態解析（高速度画像装置を用いた可視化、圧測定））および理論解析を継続するとともに、模擬モデル実験では、単純閉鎖空間内で発生する衝撃波による生体内伝播衝撃波の減弱効果を材質、壁面計状の変化による効果を可視化、圧測定および理論解析で行うとともに、複雑閉鎖空間内の衝撃波伝播動態・模擬生体内衝撃波伝播動態解析（可視化、圧測定）に着手した。次年度理論解析も推進し、衝撃波の体内伝播動態の解明と外傷性脳損傷を防止手段の構築をすすめる。
自由飛行物体にかかる非定常空気力を明らかにする非定常マルチカラーPSP技術の実現

沼田大樹, 菊池崇将, 水書稔治, 大谷清伸

Offer Organization: 日本学術振興会

System: 科学研究費助成事業基盤研究(B)

Category: 基盤研究(B)

Institution: 東海大学

2020/04/01 - 2023/03/31

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本研究では、自由飛行物体にかかる非定常空気力を明らかにする非定常マルチカラーPSP技術の実現を目指し、2020 年度に引き続き感圧塗料及び計測方法の双方において開発を進めた。 2021 年度において、感圧塗料の開発としては、従来型の感圧塗料の改良に引き続き取り組んだが、特に感圧塗料塗装時の特性のばらつきを抑える目的で、その塗装方法に大幅な改良を施した。結果として特性安定性を確保することに成功し、今後のマルチカラーPSP技術の確立に向け大きな進展とはなったが、一方で幾つかの技術的な課題点も明らかとなった。2022 年度においては、それらを次年度の研究で解消する計画である。計測系については、2021 年度において撮像光学系を見直し、より計測条件が厳しい計測対象であっても感圧塗料からの発光を取得しやすく、かつ信号雑音比を大幅に改善可能な計測系へと改良した。この改良に伴い、従来型の光学系を用いた計測結果に比べ、大幅に計測精度を向上することに成功した。結果としてその後の解析精度も向上したが、2022 年度においては感圧塗料の特性と併せて更なる最適化を図る予定である。実証試験については、当初実証試験に用いることを想定していた外部機関の試験装置がコロナ禍のために使用できず、実証試験から得られる予定であった感圧塗料・計測手法に関するフィードバックが得られなかったため、感圧塗料及び計測方法の双方について限られた向上にとどまらざるを得なかった。
Development of a weak shock wave pulse jet scalpel that achieves both local control of infiltrating lesions and preservation of postoperative function

Nakagawa Atsuhiro

Offer Organization: Japan Society for the Promotion of Science

System: Grants-in-Aid for Scientific Research

Category: Grant-in-Aid for Scientific Research (A)

Institution: Tohoku University

2018/04/01 - 2021/03/31

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The purpose of present study was to achieve infiltration of drug delivery to brain parenchyma through neuroendoscopic procedure by applying pulsed water jet. We have hypothesized that the penetration depth and area can be modified by applying shock wave. We have measured material property of brain and measured penetration depth and area using brain phantom and animal model. Present results showed the possibility of shock wave modified pulsed water jet can be additional treatment tool for the malignant lesion without well demarcated margin.
Development of a new piezo-actuator pulsed water jet system that facilitates easy resection of liver tissue, from hepatic cirrhosis to fatty liver

Nakanishi Chikashi

Offer Organization: Japan Society for the Promotion of Science

System: Grants-in-Aid for Scientific Research

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2018/04/01 - 2021/03/31

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Biochemical and histological findings in rat hepatectomy experiments demonstrated that the use of a piezo-actuator pulsed water jet system (ADPJ) in liver resection reduced postoperative liver damages when compared with the use of existing instruments. In experiments using resected human tissues, it was shown that the rupture stress values in liver parenchyma, including hepatic cirrhosis, were lower than rupture stress values in liver tumor capsules, hepatic veins, and Glisson's sheath. Moreover, the relationship between the drive voltage of the ADPJ and rupture stress values in resected tissues and the depth of incision were investigated. Preservation of blood vessels with ADPJ was demonstrated using resected porcine livers and the speed of incision was shown to be significantly faster than that of the existing instruments. In this study, the benefits of ADPJ in liver resection, including hepatic cirrhosis, in comparison with existing ultrasonic surgical instruments were demonstrated.
Development of a new controlled shock wave pressure generation method by using a closed space made of materials with different acoustic impedance Competitive

Ohtani Kiyonobu

Offer Organization: Japan Society for the Promotion of Science

System: Grants-in-Aid for Scientific Research

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2018/04/01 - 2021/03/31

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In this study, an experiment and numerical simulation on underwater shock wave generation phenomena by an explosion in a closed space for establishment of a new controlled shock wave pressure generation method related to the shock wave medical and biomedical application. Underwater shock wave was generated in a metal tube as a closed space made of material with different acoustic impedance. The process of underwater shock wave generation phenomena from a metal tube was visualized by the shadowgraph method. The pressure history of generated shock wave was measured simultaneously by a pressure sensor. The process of underwater shock wave interaction phenomena with a metal tube inside wall was simulated. The peak overpressure of induced underwater shock wave from a metal tube was larger than that of shock wave by detonating in water open space. The peak overpressure of shock wave in a stainless-steel tube was higher than in an aluminum tube due to difference in acoustic impedance.
Long-Range Flow Visualization with High-Spatial Resolution by Background-Oriented Schlieren Method Combined with Adaptive Optics

Mizukaki Toshiharu

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (B)

Institution: Tokai University

2017/04/01 - 2020/03/31

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To obtain quantitative fluid dynamical information on phenomena that are not reproduceable in wind tunnels, including sonic boom, quantitative visualization method that is able to visualize the flow around aircrafts with high spatial resolution has been studied. The light including information on the flow field will be distorted through atmospheric turbulence at an observer. Firstly, to determine specification of new adaptive optics, the authors have developed a laser scintillation measurement system for the atmospheric turbulence near ground using relatively simplified equipment. Secondary, base on the characteristics of the atmospheric turbulence near ground, an adaptive optics for background-oriented schlieren (BOS) that is able to visualize large-scale fluid dynamical phenomena around aircrafts, has been developed and merged to the BOS. Finally, the authors have successfully made spatial resolution improved by four times.
Development of new stent for the treatment of intracranial fusiform aneurysms to cure the aneurysmal wall and preserve perforators

Endo Hidenori

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2017/04/01 - 2020/03/31

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Using the data obtained from the human cases, we performed computational fluid dynamics (CFD) analysis. We calculated wall shear stress, oscillating shear index, relative residence time of the aneurysm to standardize these parameters. Then, We calculated the appropriate condition to cure the pathology of the aneurysmal wall and to preserve the perforators based on the theory of fluid engineering. We developed the design of the stent which can meet above mentioned condition based on the CFD data. We tried to create prototype stent to deploy into the aneurysm animal model to validate the proper design of the stent.
Development of Molecular-Imaging Technique for Investigating Pressure-Field on the Surface of the Supersonic Projectiles

Numata Daiju

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (B)

Institution: Tokai University

2016/04/01 - 2019/03/31

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In this study, as a new technology to realize pressure-field measurement on free-flight projectiles flying at supersonic speed, we developed the ultrafast-response bi-luminophore pressure-sensitive paint and developed a special two-wavelength splitter optical system. In addition, to conduct ballistic-range experiment using these developed techniques, we also worked on an optical system design for detecting the light emission with a high-speed camera equipped with a two-wavelength splitter optical system. In experiment, we succeeded in simultaneously detecting two wavelength images of emission from free-flight projectiles required for pressure calculation with a high-speed camera. In addition, by analyzing these two wavelength images, we also succeeded in clearly reproducing the pressure field on the surface of free-flight supersonic projectiles.
Reduction effect of explosion hazard and investigation of pressure attenuation of underwater explosion by porous complex mediums

KITAGAWA Kazutaka

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Aichi Institute of Technology

2016/04/01 - 2019/03/31

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Interaction between underwater explosion and complex media is the research topics related to injure the strong force loading in structures for undersea operation and underwater works from explosion hazards. Attenuation and reduction performance depend on structural shape, compression strength, porosity, porous structure and acoustic impedance. The research is predicting for the pressure and impulse attenuation of underwater explosion environment. Porous compressible material will be able to disperse the pressure, inertia, momentum and impulse of shock loading, bubble pulse, and bubble jet of underwater explosion. Results show that porous semicircle wall shows good performance with attenuation of underwater explosion environment.
Infiltrative drug delivery by additional application of shock wave on pulsed water jet.

NAKAGAWA Atsuhiro

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (B)

Institution: Tohoku University

2015/04/01 - 2018/03/31

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Water jet dissection has been clinically applied to achieve maximum resection of well-demarcated lesion under preservation of small vessels. However, removal of infiltered lesion is still challenging. On the other hands, shock waves (SW) changes permeability of membrane transiently. The purpose of present study is to develop pulsed water jet that can infilter the liquid from the surface of dissection plane using low overpressure SW which do not cause brain damage. Pulsed water jet+ SW have been applied in the swine brain after development of prototype of generator. Relationship between energy, frequency, and water amount were evaluated by high speed photography, pressure measurement, and test in phantom model. The histological specimen and intraoperative finding showed the infiltration of pigmented liquid into brain parenchyma without significant damage as deep as 3 mm. Present results showed possibility of injecting drug into brain parenchyma without significant brain damage using SW.
Development of the piezo-actuator pulsed water jet system for laparoscopic liver resection

Nakanishi Chikashi, YOKOSAWA Tomoki

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2015/04/01 - 2018/03/31

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We assessed the feasibility of a newly developed, piezo actuator driven pulsed water jet (ADPJ) for laparoscopic liver resection in swine model. Laparoscopic liver resection was safely performed using ADPJ without increasing surgical duration or blood loss. And we built a prototype of ADPJ with three nozzles to improve resection speed. ADPJ with three nozzles improved resection speed, but it was noted experimentally that its resection speed depends on the driving voltage and pulse frequency. The physical properties of human liver were evaluated. There were significant differences in the breaking strength among three groups (cirrhotic liver parenchyma, hepatic vein, and Glisson’s sheaths). It was suggested that ADPJ can be used for liver resection in cirrhotic patients. Furthermore, animal experiments using rat model showed that ADPJ attenuate hepatic damage more than ultrasonic surgical aspirator after liver resection.
Experimental application of pulsed liquid jet for neuroendoscopic surgery for pituitary lesion.

OGAWA YOSHIKAZU

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2015/04/01 - 2018/03/31

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Neuroendoscopic surgery allows minimally invasive surgery, but lacks effective methods to control bleeding. Water jet dissection with continuous flow has been used in liver and kidney surgery, and is effective for tissue manipulation with vascular and nerve preservation, but involves some potential risks during application in the deep brain lesion. The purpose of present study is to develop pulsed laser-induced liquid jet (LILJ) that can be incorporated into neuroendoscopic surgery. LILJ have been applied in the swine ventricle after development of prototype of LILJ generator for neuroendoscopy application. Relationship between laser energy, standoff distance between tip of optical fiber and nozzle, nozzle aspect ratio, and contrability of splash were evaluated by high speed photography, pressure measurement, and test in phantom model. The histological specimen and intraoperative finding showed the preservation of small vessels during ventricle wall dissection.
Development of off-clamp partial nephrectomy using a piezo actuator-driven pulsed water jet system

Yamashita Shinichi, KAMIYAMA Yoshihiro, FUJII Shinji

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2015/04/01 - 2018/03/31

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We have developed a novel surgical device, a piezo actuator-driven pulsed water jet (ADPJ) system to improve the renal function after partial nephrectomy (PN) for renal cell carcinoma. The breaking strength of renal capsule or the renal calix was higher than renal parenchyma in the swine. By setting ADPJ pressure to renal parenchymal intensity, off-clamp laparoscopic PN using the ADPJ system could be performed with little bleeding. Also, the ADPJ system resulted in less renal damage after off-clamp PN than existing thermal coagulation devices in a rat model. Finally, the breaking strength of the pseudo tumor capsule was higher than that of renal parenchyma in human kidney. If the ADPJ pressure was set to the same intensity of renal parenchyma, the ADPJ system might dissect the renal parenchyma safely, not injured the pseudo tumor capsule.
新規パルスジェットメスを用いた内視鏡下肝臓手術の開発 Competitive

中西史

Offer Organization: 日本学術振興会: 科学研究費補助金

System: 基盤研究（Ｃ）

2015/04 - 2018/03
組織切開・形態学的温存下に切開面周囲に薬液浸潤可能な衝撃波メスの開発 Competitive

中川敦寛

Offer Organization: 日本学術振興会: 科学研究費補助金

System: 基盤研究（Ｂ）

2015/04 - 2018/03
Low overpressure shock wave for treatment in the deep brain

TOMINAGA Teiji

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (B)

Institution: Tohoku University

2014/04/01 - 2017/03/31

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The purpose of present study is to clarify the effect of low overpressure shock wave (SW) in the central nervous system and to obtain basic understanding for development of drug delivery system using SW in the deep brain lesion. We first applied low overpressure SW in the animal brain and evaluated histological findings. We also evaluated the wave propagation in the brain phantom using high speed photograph and pressure measurement. We then made prototype for low overpressure SW applicator and applied dye liquid in the porcine brain after craniotomy and showed that application of low overpressure SW enhances the distribution of dye compared to mere injection of small amount liquid.
Experimental demonstration of unsteady detatched shock wave and theory development toward its active control

Ohnishi Naofumi

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2014/04/01 - 2017/03/31

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An instability of a detached shock wave formed in front of a blunt body was investigated by numerical simulations and experiments using a ballistic range toward an engineering application of unsteady shock waves. The experiments successfully demonstrated that the detached shock wave is unstable under low-specific-heat-ratio and high-Mach-number conditions, and the numerical simulations were able to predict the critical condition of the instability. Moreover, the front shape of the projectile equipped with an edge is preferable to destabilize the detached shock wave, and acoustic waves emitted from the edge play a significant role on inducing the instability.
Development of a new dissection device for deep-seated brain tumor using pulsed water-jet system.

Kawaguchi Tomohiro

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2014/04/01 - 2017/03/31

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To achieve safe and effective resection for deep-sheeted brain tumor, we developed a new dissecting device using pulsed water jet system. During this study period, we focused on the lesions located inside of the ventricle system, which are one of the most difficult targets to approach. We have already reported the reduced operation time and increased resection rate by using pulsed water jet device for pituitary surgery. Compared the former evidences, there were two essential points; 1) unique shape of the device to approach inside of the ventricle, 2) anatomical characteristics of the ventricles, which are totally filled with cerebrospinal fluid. We developed long, wire-shaped devices for flexible neuroendoscope. We also optimized the condition to eject water jet inside of the cerebrospinal fluid. As a result, we revealed the preclinical proof of concept that water jet device with flexible neuroendoscope can achieve effective tissue dissection with preserving large and small vessels.
Pulsewater jet for spinal cord dissection

ENDO TOSHIKI

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2014/04/01 - 2017/03/31

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In this project, ｓurgical instruments for simultaneously achieving tumor removal and spinal cord function preservation during spinal tumor removal surgery; pulse jet female was developed. It was possible to practice the incision of the porcine spinal cord and to optimize the pulse jet female. As a result, confirmation of safety and effect of the device can be confirmed, and findings leading to future clinical applications could be obtained.
Understanding of shock wave propagation phenomena in human body by using the simulated biomedical materials with different acoustic impedance Competitive

OHTANI Kiyonobu, NAKAGAWA ATSUHIRO, ABE ATSUSHI

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2014/04/01 - 2017/03/31

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In this study, an experiment and numerical simulation on interaction of underwater shock wave at the interface of materials with different acoustic impedance was performed, for an establishment of the fundamental research base for the development to the shock wave medical and biomedical application related to human tissue damage by shock wave interacting human body, and the shock wave bioengineering application about a shock wave sterilization technology. Shock wave interaction phenomena with the interface impedance was visualized by the shadowgraph method and recorded by an ultra-high-speed camera at high spatiotemporal resolution. The shock wave pressure history near the interface was measured simultaneously by a pressure sensor with high spatiotemporal resolution. The process of shock wave interaction with the interface was numerically simulated. The experimental and numerical results obtained is useful for understanding shock wave interaction phenomena with the interface.
CO2レーザ照射による超臨界水雰囲気高温岩体の掘削システム開発 Competitive

小林俊雄

Offer Organization: 独立行政法人新エネルギー・産業技術総合開発機構

System: エネルギー・環境新技術先導プログラム

2015 - 2017/03
Atunuation effect of underwater explosion by porous media

Kazutaka Kitagawa, OHTANI Kiyonobu, ABE Atsushi, NAGAHIRO Daiki, NOMURA Tatsuya

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Aichi Institute of Technology

2013/04/01 - 2016/03/31

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Collision of underwater explosion and any shape body is one of the research topics related to attenuate the shock environment in any structures for disaster prevention from from strong explosion hazards. This study is the attenuation and reduction effect of underwater explosion, bubble pulsation and bubble jet flow near the complex boundaries. A gas bubble is producing by the explosive. It is expanding the ellipsoid shape by effect of moving boundary of foam. At contraction phase, a gas bubble is moving to downward and bubble jet flow is generating apart from a foam surface by weak downward flow.Time histories of total stress (sum of contact stress of foam skeleton, gas pressure and hydraulic pressure) in foam is demonstrated a stress which is smaller than that due to the rigid wall. Total stress in foam attenuated up to 99 % of peak dynamic pressure in rigid wall. Attenuation of underwater explosion could attenuate and mitigate by using porous compressible foam.
Development of plasma nano-bubbles with modified antibody for induction of apoptosis

SATO Takehiko, MIYAHARA Takashi, OHTANI Kiyonobu, YOSHINO Daisuke

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Challenging Exploratory Research

Institution: Tohoku University

2013/04/01 - 2015/03/31

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The underwater discharge device which produces a large amount of microscopic bubbles was accomplished by installing the insulation-coated needle-like and ring-shaped platinum wire electrodes in the ultrapure water and applying the high voltage to the needle electrodes. It has been shown that these bubbles generated a particle size distribution with a greatest frequency of particle size of 100 - 200 nm. Also, a verification method for ultrafine bubbles that was impossible for solid-gas determination was developed by developing the devices that pressurizes and observes the bubbles with a maximum of 100 atm in order to distinguish solid impurities such as electrode materials and the ultrafine bubbles, and that observes bubble deformation using shock waves. By these results, we proposed an important fundamental technology toward modification of antibodies of nano-bubbles.
Induction mechanism of targeted gene expression by controlling spatiotemporally plasma flow at biological interface

SATO Takehiko, JOHKURA Kohei, OHARA Taku, KANAZAWA Seiji, MIYAHARA Takashi, KOMIYA Atsuki, OHTANI Kiyonobu, YOSHINO Daisuke

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (A)

Institution: Tohoku University

2012/04/01 - 2015/03/31

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The development of the formation and controlling method of the self-preserving plasma flow were accomplished by development of the high-speed high-voltage power supply, visualization system which had a very high spatiotemporal resolution and high accurate synchronous measurement system of the plasma characteristics. It has been shown that the self-preserving plasma flow makes a microscopic bubble cluster at the tip of the electrode several hundred nanoseconds after the voltage was applied, then starts propagation intermittently with a speed of about 2 kilometers per second from the tip of the protrusion of the bubbles synchronously with the pulsed discharge current. As for the induction of gene cluster expression, it has been shown by the comprehensive gene analysis that the gene cluster with functions of metabolism, immunity, regeneration, etc. expressed by weak plasma stimuli, which was different from hydrogen peroxide which was a main cause of the plasma stimuli.
Application of pulsed water jet for tumor removal through transsphenoidal approach: Evaluation of nerve preservation

OGAWA Yoshikazu, TOMINAGA Teiji, NAKAGAWA Atsuhiro, WASHIO Toshikatsu, ARAFUNE Tatsuhiko, OHTANI Kiyonobu

Offer Organization: Japan Society for the Promotion of Science

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

Category: Grant-in-Aid for Scientific Research (C)

Institution: Tohoku University

2012/04/01 - 2015/03/31

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Water jet technology provides tissue dissection with preservation of fine blood vessels. The purpose of present study is to evaluate functional preservation of peripheral nerves and dissection under intraoperative electrophysiological monitoring in patients with skull base tumors manifesting as severe visual disturbance through the extended transsphenoidal approach using pulsed laser-induced liquid jet (LILJ) system. Intraoperative visual evoked potential (VEP), and pre/postoperative conventional visual assessments were investigated. Precise dissections of the tumor were obtained, resulting in gross total removal. Most of the cases showed immediate improvement on intraoperative VEP and showed good recovery at discharge, and all patients evaluated had recovered good visual status. The LILJ system can achieve safe and optimal removal with functional preservation of optic nerves, probably because of the high resistance of the arachnoidal sheath and fine vascular tissue.
地熱井レーザ掘削方式の基盤研究 Competitive

小林俊雄

Offer Organization: 独立行政法人科学技術振興機構

System: 研究成果展開事業（研究成果最適展開支援プログラム（A-STEP））

2013 - 2014/03
CO2レーザ照射による水中環境下でのレーザ誘起現象を利用した岩石加工技術の土木・原子力設備解体への適用性研究 Competitive

小林俊雄

Offer Organization: 独立行政法人科学技術振興機構

System: 研究成果展開事業（研究成果最適展開支援プログラム（A-STEP））

2011 - 2013/03

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Social Activities 1

NHKスペシャル知られざる衝撃波～長崎原爆・マッハステムの脅威～

2014/08/18 -

Media Coverage 1

子供の科学

誠文堂新光社　子供の科学　なぜなぜどうして？音と同じ速さで平行に進んだら、音はどう聞こえるの？（pp.58）

2017/08/10

Type: Newspaper, magazine