Diffraction of a spherical acoustic wave due to the coupling of pressure release and absorbing half planes in a moving fluid

We investigate the diffraction of a spherical acoustic wave (emanating due to a point source) from the coupling of a pressure release half plane characterized by zero impedance (soft half plane) and an absorbing (locally reacting) half plane satisfying Myers' impedance condition in a moving fluid. Myers' condition (a generalization of Ingard's impedance condition) is now the accepted form of the boundary condition for impedance barriers with flow and yields a correct form of the diffracted field. The method of solution is based on the Wiener-Hopf technique and asymptotic approximation methods.