Propagation from a point source over a rough finite impedance boundary

Abstract

Measurements of the excess attenuation of sound from a point source over artificially rough surfaces in an anechoic chamber are compared with predictions from modified forms of theories by Howe [J. Sound Vib. 98, 83–94 (1985)] and by Tolstoy [J. Acoust. Soc. Am. 72, 960–072 (1982)]. The modified theories agree with each other and are in tolerable agreement with data over hard or nearly hard boundaries. The modified Tolstoy formulation, which allows the roughnesses to have an impedance that differs from the impedance of the surrounding plane, is found to give better agreement with data for propagation over rough finite impedance surfaces.