| Project/Area Number |
06651085
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
海洋工学
|
|---|
| Research Institution | KYUSHU UNIVERSITY |
|---|
Principal Investigator |
KYOZUKA Yusaku Kyushu University, Interdiscip.Grad.School of Eng.Sci., Professor, 大学院・総合理工学研究科, 教授 (80177948)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
NAKAMURA Masahiko Kyushu University, Res.Inst.Appl.Mech., Asso.Professor, 応用力学研究所, 助教授 (40155859)
KOTERAYAMA Wataru Kyushu University, Res.Inst.Appl.Mech., Professor, 応用力学研究所, 教授 (80038562)
|
|---|
| Project Period (FY) |
1994 – 1995
|
| Project Status |
Completed (Fiscal Year 1995)
|
| Budget Amount *help |
¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1995: ¥900,000 (Direct Cost: ¥900,000)
|
|---|
| Keywords | Wave-Free Body / Wave-Free Singularity / Wave Free / Wave Diffraction / Shallow Water / Boundary Element Method / 波無し浮体形状 / 半潜水式海洋構造物 / 波浪強制力 / 浅海域 / 浮体 / 波特異点 |
|---|
| Research Abstract |
Some wave-free floating-body forms in heaving oscillation are obtained by using a wave-free singularity of source and vertical dipole combination to generate bulbous-shaped two-and three-dimentional bodies in shallow water. Body forms are obtained by the streamline tracing method at a planned wave frequency, where the body boundary condition of heaving oscillation is satisfied.
Effects of location of the wave-free singularity and water depth on the body-form are studied. Body forms become slender as water depth becomes shallow. Wave exciting forces of obtained bodies are calculated by the singularity distribution method in two-and three-dimentions to verify that they become wave-free at the planned wave-number.
Model experiments were conducted in 2D and 3D wave tanks. Wave exciting forces of obtained wave-free bodies were measured in regular waves. Wave-free frequency estimated by amplitude reaponse function of heaving excitation is almost same as the theory but a little bit higher, which may be attributed to nonlinear effects such as viscosity of water. Finally, some proposal are made to apply such a wave-free body to a very large floating structure (VLFS) of semi-submersible type.
|
