Finite element analysis of the propagation of acoustic waves in waveguides

Abstract A bidimensional mathematical model is developed to study the propagation of acoustic waves in waveguides. First, the theoretical formulation is presented for the case of a linear waveguide. The problem is reduced to a bidimensional problem, where only the cross-section of the guide is meshed by using finite elements. Then, the method is extended to the case of a circular waveguide of constant curvature. After the validation of the method for simple cases, a wedge guide, the top angle of which is variable, is studied, and the finite element results are compared to experimental ones, demonstrating the accuracy of the model. Finally, it is indicated how this approach could be extended to waveguides of any cross-section, for application in signal processing devices, in geophysics and underwater acoustics, as well as in solid surface physics.