Project/Area Number |
12305031
|
Research Category |
Grant-in-Aid for Scientific Research (A)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
水工水理学
|
Research Institution | Osaka City University |
Principal Investigator |
KAKUNO Shohachi Osaka City University, Faculty of Engineering, Professor, 大学院・工学研究科, 教授 (70047398)
|
Co-Investigator(Kenkyū-buntansha) |
ASAI Kouji Yamagata University, Faculty of Eng., Assistant Professor, 工学部, 助教授 (70202570)
ETOH Goji Kinki University, Faculty of Science and Eng., Professor, 理工学部, 教授 (20088412)
SUGIHARA Yuji Kyushu University, Int.Grad.School of Eng., Sci., Ass.Prof., 大学院・総合理工学研究院, 助教授 (70243970)
TAKEHARA Kosei KInki University, Faculty of Science and Eng., Ass.Professor, 理工学部, 助教授 (50216933)
YOSHIOKA Hiroshi Kyoto University, Disaster Prevention Res.Inst., Res.Assist., 防災研究所, 助手 (10027287)
細井 由彦 鳥取大学, 工学部, 教授 (50127859)
中村 由行 独立行政法人港湾空港技術研究所, 海洋水工部・沿岸生態研究室, 室長(常勤研究職) (90172460)
|
Project Period (FY) |
2000 – 2002
|
Project Status |
Completed (Fiscal Year 2002)
|
Budget Amount *help |
¥26,930,000 (Direct Cost: ¥23,900,000、Indirect Cost: ¥3,030,000)
Fiscal Year 2002: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000)
Fiscal Year 2001: ¥8,580,000 (Direct Cost: ¥6,600,000、Indirect Cost: ¥1,980,000)
Fiscal Year 2000: ¥13,800,000 (Direct Cost: ¥13,800,000)
|
Keywords | wave breaking / air bubble / gas transfer velocity / wind-wave / air-sea interface / PTV / high-speed camera / void probe / 乱流モデル / 振動格子乱流場 / 超音波 |
Research Abstract |
A dual-tip void probe was developed as a extension of standard single void probe. The validity of dual-tip void probe was verified and applied to bubble characteristics induced by breaking wave in the mechanically generated wave in the flume. The amount of gas transfer flowing rate instead of traditional gas transfer velocity was proposed to estimate the gas transfer rate in the surf zone, quantitatively (Kakuno, Shigematsu and Hosoi). The characteristics of turbulence in bubbly flows were measured and analyzed in the experimental facility (Asai). The droplet collision into the water surface was measured using 1 million frame per second ultra-high speed camera. The instability of thin gas film between droplet and water surface shows clear Reynolds number and Weber number dependence (Etoh). The relationship between the surface renewal process and micro scale turbulence has been measured by Particle Image Velocimetry and Laser Induced Fluorescence in a lattice turbulence (Sugihara). The simultaneous visualizations of air and water velocities were conducted in the wind-wave flume. The organized motion of air and water flows were measured and the bursting motions of air flow into the water were observed visually (Takehara, Etoh, Shigematsu and Tsujimoto). The bubble diameter distribution and bubble source functions were measured using Phase-Doppler anemometry in the wind-wave flume. The coherent bubble diameter spectra were measured under the wind-wave breaking (Mori). The field observations of bubble distributions under the wind-wave breaking were investigated using ultra sonic sensor at the upper ocean (Yoshioka). The gas transfer model at the breaking wave interface was proposed as a summary of above results (Moog).
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