The null-field approach and the propagation of elastic surface waves along cylindrical cavities

The existence of surface wave modes, propagating along an infinite cylindrical cavity of general, constant cross section is demonstrated for two non-elliptic geometries. The method used is the null-field approach with global expansions of the surface displacement. The use of Fourier expansions for the surface fields is carefully investigated. Numerical results are presented for the phase velocities and the surface displacements.