Diffraction of Water Waves by A Vertically Floating Cylinder in A Two-Layer Fluid

• 作 者: SHI Qiang YOU Yun-xiang MIAO G
• 机 构: State Key Laboratory of Ocean Engineering
• 出 处: 中国海洋工程（英文版）
• 发表日期: 2004年期
• 关键词: two-layer fluid vertically floating cylinder hydrodynamic loads surface-wave mod
• 基金项目: 国家高技术研究发展计划(863计划);国家自然科学基金

In this paper, the diffraction of water waves by a vertically floating cylinder in a two-layer luid of a finite depth is studied. Analytical expressions for the hydrodynamic loads on the vertically floating cylinder are obtained by use of the method of eigenfunction expansions. The hydrodynamic loads on the vertically floating cylinder in a two-layer fluid include not only the surge, heave and pitch exciting forces due to the incident wave of the surface-wave mode, but also those due to the incident wave of the internal-wave mode. This is different from the case of a homogenous fluid. Some given examples show that, for a two-layer fluid system with a small density difference, the hydrodynamic loads for the surface-wave mode do not differ significantly from those due to surface waves in a single-layer fluid, but the hydrodynamic loads for the internal-wave mode are important over a wide range of frequencies. Moreover, also considered are the free surface and interface elevations generated by the diffraction wave due to the incident wave of the surface-wave and internal-wave modes, and transfer of energy between modes.