分层流体中内孤立波在潜浮式竖直薄板上透射和反射

采用边缘层理论研究了两层流体系统中内孤立波在潜浮式竖直薄板上的透射和反射问题,提出了非线性演化方程的“初值”条件,分析了内孤立波与薄板非线性相互作用的效应。研究表明:流体层的密度比以及薄板伸入上下层的深度对于反射和透射波结构具有显著的影响,薄板伸入下层越深、密度差越小,则薄板阻碍孤立波透射的效率越高;透射波通常演化为单峰孤立波和迅速衰减的尾波,反射波演化为缓慢衰减的尾波列;对于具有小密度差的跃层结构,内孤立波在潜浮式竖直薄板上的透射及其演化近乎是无障碍的。

Transmission and reflection of internal solitary wave past a submerged vertical thin barrier floating in a stratified fluid

Based on the edge layer theory,the transmission and the reflection of an internal solitary wave past a submerged vertical thin barrier floating on the interface of a two-layer fluid system are investigated.A problem of the 'initial' value for the nonlinear evolution equation is proposed.It follows that there exist obvious effects of the density ratio and the depth of the barrier into the upper-or lower-layer on the structures of transmitted and reflected waves.It is also found that both the large depth of the barrier into the lower layer and the small density difference between the upper and lower fluids can raise the blocking efficiency to the internal solitary wave.The transmitted wave usually evolves into a single peak soliton with an oscillating tail which is found to decay rapidly,and the reflected wave into a slowly decaying wave train.In a two-layer fluid with very small density difference,an internal solitary wave can pass over the vertical thin barrier as if it were transparent.