Acoustic diffraction by a disk in a viscous medium

Abstract

The diffraction of a time-harmonic acoustic plane wave by a circular disk in a viscous fluid medium is considered by using the linearized equations of viscous fluid flow and the no-slip condition on the rigid disk. Sets of dual integral equations for the fluid velocity and pressure are derived for an arbitrary disk radius and an arbitrary angle of incidence. The dual integral equations are solved by an analytic reduction to sets of linear algebraic equations. In the cases of normal or tangential incidence, numerical results are presented for the fluid velocity in the plane of the disk and the scattered acoustic disturbance in the far field.