| Project/Area Number |
15360468
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Naval and maritime engineering
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| Research Institution | KYUSHU UNIVERSITY |
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Principal Investigator |
KASHIWAGI Masashi Kyushu University, Research Institute for Applied Mechanics, Professor, 応用力学研究所, 教授 (00161026)
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| Co-Investigator(Kenkyū-buntansha) |
HU Changhong KYUSHU UNIVERSITY, Research Institute for Applied Mechanics, Associate Professor, 応用力学研究所, 助教授 (20274532)
SUEYOSHI Makoto KYUSHU UNIVERSITY, Research Institute for Applied Mechanics, Research Associate, 応用力学研究所, 助手 (80380533)
NAKAMURA Masahiko KYUSHU UNIVERSITY, Research Institute for Applied Mechanics, Associate professor, 応用力学研究所, 助教授 (40155859)
TAKAGI Ken Osaka University, Faculty of Engineering, Associate Professor, 大学院・工学研究科, 助教授 (90183433)
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| Project Period (FY) |
2003 – 2005
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| Project Status |
Completed (Fiscal Year 2005)
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| Budget Amount *help |
¥9,200,000 (Direct Cost: ¥9,200,000)
Fiscal Year 2005: ¥2,600,000 (Direct Cost: ¥2,600,000)
Fiscal Year 2004: ¥3,300,000 (Direct Cost: ¥3,300,000)
Fiscal Year 2003: ¥3,300,000 (Direct Cost: ¥3,300,000)
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| Keywords | Water on deck / Green water / Breaking wave / Entrainment of air / Wave impact / CIP method / Computational Fluid Dynamics / MPS法 |
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| Research Abstract |
(1)With the CIP (Constrained Interpolated Profile) method used as a basis, a computer program (which was recently named as RIAM-CMEN : Computation Method for Extremely Nonlinear hydrodynamics) was developed and its validation was conducted. For a fundamental dam-breaking problem, validity of the interface capturing scheme and the effects of compressibility and surface tension of a fluid were checked in detail. Then the time history of the pressure measured at the side wall of a rectangular tank was compared with corresponding results by the numerical computation. Furthermore, wave-induced motions with water on deck of a 2-D floating body were measured and compared with corresponding results by the developed computer program. The overall result of comparison was favorable, but a close comparison suggests that further research is needed for accurate prediction of the pressure on the body surface in the framework of Eulerian rectangular grids.
(2)The computer program, RIAM-CMEN, was extend
… More
ed to simulate the motions of a 3-D ship advancing with a constant speed and oscillating in high-amplitude waves, and computed results were demonstrated as an animation. To validate these computed results, a ship model of 2.5 m in length was manufactured, and measurement was performed for the pressure on the horizontal deck and vertical wall due to the green-water-on-deck and for wave-induced motions of a ship at Fn=0.0, 0.15, and 0.20 and for wavelengths of λ/L=0.75, 1.0, and 1.25, for both cases of ship motions (surge, heave, and pitch) being completely fixed and free to respond to the incident wave.
(3)The MPS (Moving Particle Semi-implicit) method, which is also a promising method for extremely nonlinear hydrodynamic problems, was also validated through comparisons with experimental results for the sloshing in a tank and motions of a 2-D floating body including the water-on-deck phenomenon in large waves. Improvement was achieved for the calculation method of the pressure by introducing an auxiliary scheme for calculating the velocity. Acceleration of the numerical computation was also achieved with a parallelization technique for the computer program, and it was confirmed that the expected relation between the number of CPU and the reduction rate in the computation time was almost the same as that predicted. Less
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