Reflection of acoustical waves at porous boundaries

Abstract

The reflection and transmission of plane harmonic waves impinging from air to the plane face of porous material occupying a semi-infinite space as well as with finite thickness is considered. The variation of these coefficients with the angle of incidence and various parameters (frequency, permeability, etc.) is illustrated for certain porous materials. The results obtained indicate that the transmission coefficient remains the same under the assumption of velocity potential (there is no velocity potential in general in the porous material) while the reflection coefficient changes significantly. Subject Classification: [43]20.30, [43]20.35.