Frequencies and Modes of the Helmholtz Equation With Zero Normal Derivatives in Isosceles Triangular and Rhombic Domains

Abstract

The two-dimensional Helmholtz equation with zero normal derivatives on the boundary is studied using boundary collocation. The frequencies and modes are found for the isosceles triangular and rhombic domains. The solutions are important in predicting the standing waves in containers and also the transverse electric (TE) waves of electromagnetic, optical, and acoustic wave guides.