Effects of porous boundaries on the dynamics of an inviscid vortex filament (Q2709605)

The path of a weak incompressible vortex filament, and hence its velocity are studied by means of Fourier transform and conformal mapping techniques in the presence of a porous material. The porous material is characterized by its flow resistance and by effective fluid density within its lattice. The author studies the variation of vortex velocity depending on the flow resistance, effective fluid density, and the properties of boundaries. The study is then extended to include the effect of a flow boundary discontinuity where the flat surface is made up of a rigid and a porous surface. The results illustrate that there is a relatively rapid change in vortex acceleration when the vortex moves across the plane of discontinuity, suggesting the possibility of sound generation close to this instant.