Diffraction by an acoustically penetrable or an electromagnetically dielectric half plane

Abstract

The present work gives a mathematical model for an acoustically penetrable or electromagnetically dielectric half plane. An approximate boundary condition is derived which depends on the thickness and material constants which constitute the half plane. A solution is obtained, using the approximate boundary condition, for the problem of diffraction of a line source by a semi-infinite penetrable/dielectric half plane. The mathematical problem which is solved is an approximate model for a noise barrier which is not perfectly rigid and therefore transmits sound. It is shown that for wood or plastic barriers the transmitted sound level is proportional to the quantity (incident sound wave length/barrier thickness). Thus for a given barrier thickness the low frequency sound is transmitted more than the high frequency sound.