On wave propagation in an inhomogeneous non–stationary medium with an inhomogeneous non-stationary flow

Abstract

An approximate wave equation that models scalar wave propagation in a moving fluid whose ambient properties and flow are inhomogeneous both in space and time is considered. Asymptotic solutions for both non–caustic and caustic regions and some Hamiltonian properties of the equation in both non–caustic and caustic regions are developed.