Internal Waves Excited by a Moving Source in a Medium of Variable Buoyancy

Abstract

The problem of the far field of internal gravity waves generated by an oscillating point perturbation source moving in a vertically infinite layer of a stratified medium of variable buoyancy is considered. The analytical solution of the problem is obtained by two ways for a model quadratic buoyancy frequency distribution. In the first case the solution is expressed in terms of the eigenfunctions of the vertical spectral problem and the Hermite polynomials. In the second case the solution in the form of the Green’s characteristic function is represented in terms of the functions of parabolic cylinder. The analytical solutions obtained make it possible to describe the amplitudephase characteristics of the far fields of internal gravity waves in a stratified medium with variable Brunt-Väisäläfrequency.