On the acoustic response of a deeply corrugated periodic surface— A hybrid T-matrix approach

Abstract

The extended boundary condition (EBC) method, as proposed by Waterman [J. Acoust. Soc. Am. 5 7, 791–802 (1975)], is hybridized with the point‐matching technique in order to derive a T matrix for a periodically corrugated surface on which either the Dirichlet or the Neumann boundary condition is imposed. The limitations imposed by the Rayleigh hypothesis on Waterman’s T matrix are overcome by a correct choice of eigenfunctions for the surface field representation. Highly corrugated surfaces can now be considered. The numerical results are compared with the data computed by Holford [J. Acoust. Soc. Am. 7 0, 1116–1128 (1981)], using an integral equation method, as well as with the experimental results collected by Lacasce and Tamarkin [J. Appl. Phys. 2 7, 138–148 (1956)].