A novel numerical method for simulating wave propagation in moving media

A novel boundary integral method for simulating acoustic wave propagation in nonuniformly moving media is introduced. It is based on a generalized free-space Green´s function which utilizes parameters obtained by solving the ray-tracing equations. Inserted into the Helmholtz integral, this approximate Green´s function allows prediction of acoustic fields in moving media at low Mach numbers using the given boundary data. In order to validate the method, the acoustic field generated by a vibrating piston in a nonuniform shear flow is computed and compared with the results of a FEM simulation. Furthermore, an application of the method to simulation of wave propagation across a 2D cylindrical duct is presented.