Internal waves of stratified fluid flow over different bottom topographies

A numerical study of stratified fluid over different isolated bottom topographies in a channel of finite depth is described. Three types of stratification, i.e., ordinary two-layer, critical two-layer and uniformly stratified Boussinesq fluids are considered. A two-dimensional symmetric topography geometrically can be viewed as a combination of fore and aft parts. For a positive (negative) topography, the fore part is a forward (backward) step, whereas the aft one a backward (forward) step. The present numerical results show that a two-dimensional symmetric topography can be viewed as a combination of fore and aft parts as a forcing for internal wave generation, which is also confirmed by weakly non-linear theory.