Numerical simulation of sound scattering by a convected vortex

Abstract

The sound scattering by a convected isentropic vortex is numerically studied by solving the linearized Euler equations (LEE) with high-fidelity finite-difference methods and non-reflecting boundary conditions. Our computations are in good agreement with previous studies. Simulations for the scattering from a Taylor vortex at a range of convected velocity reveal that the convection of the vortex leads to the spectral broadening of the incident waves. The power spectral density analyses of the scattered pressure in the frequency domain show that the range of the spectral broadening is strongly influenced by convected velocity. This fact can be explained by the relative motion between the vortex and observer associated with the Doppler factor. The sidebands originating from the scattered fields at a fixed point in the frequency domain can be associated with the scattered beams observed in the case of scattering by a steady vortex.