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

作　　者：石强 尤云祥 缪国平 

机构地区：[1]Key Laboratory of Ocean Engineering, School of Naval Architecture, Ocean and Civil Engineering,Shanghai Jiao Tong University

出　　处：《China Ocean Engineering》2008年第2期181-193,共13页中国海洋工程（英文版）

基　　金：This project was financially supported by the National Natural Science Foundation of China(Grant No.10572092);the High Technology Research and Development Programof China(863Program,Grant Nos.2006AA09Z352 and 2006AA09196-6)

摘　　要：In this paper, the diffraction of water waves by a vertically floating cylinder in a two-layer fluid 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 inelude 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 interhal-wave modes, and transfer of energy between modes.In this paper, the diffraction of water waves by a vertically floating cylinder in a two-layer fluid 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 inelude 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 interhal-wave modes, and transfer of energy between modes.

关 键 词：two-layer fluid vertically floating cylinder hydrodynamic loads surface-wave mode internal-wave hurtle 

分 类 号：TV139.2[水利工程—水力学及河流动力学]