关于二层海中的二阶波浪绕射问题

On the Second Order Wave Diffraction in Two Layer Fluids

在本文中,我们用二层海模型,探讨了层化海洋中任意三维物体的二阶波浪绕射问题,给出了多色波场中二阶波浪散射势边值问题的数学提法以及基于一个弱的远场辐射条件下解的表式。同时,利用Green定理,并通过引入一个辅助势函数,我们导出了结构所受二阶波浪荷载的积分表式。结果表明,海水的层化特性对结构物所受之二阶差频波浪荷载可能具有显著的影响。

In this paper, with assumption that the stratified ocean consists of two layer fluids with different densities, the problem of the second order wave diffraction by three dimensional bodies in the stratified ocean is investigated. With the use of the regular perturbation method, the boundary value problem of the second order multi-chromatic wave scattering potential is firstly formulated, and is based on a weakly radiation condition, a formal solution of this boundary value problem is then found. By using Green theorem and introducing an assisting potential, the integral expressions, which do not explicitly connect with the second order scattering potential, of the second order wave loads are also derived. Our analysis indicates that the effects of the stratification upon the second order difference frequency wave loads on the structures may be significant.