ABSTRACT
In the last chapter, wave propagation analysis was presented for 1D isotropic longitudinal and flexural waveguides using spectral analysis. In particular, the interaction of incident waves with boundaries and constraints was presented. In this chapter, we will again use spectral analysis and apply it to two-dimensional isotropic waveguides. Introduction of an additional dimension introduces additional complexity in wave propagation. That is, it introduces a second wavenumber in the second dimension and these two wavenumbers are normally coupled. Additional dimensions also introduce additional waves. In 1D waveguides, we saw the existence of a number of wave modes, each of them identified by different wavenumbers; these were normally called temporal modes. Introduction of an additional dimension and hence the wavenumber, introduces spatial modes, which are additional waves arising out of different boundary conditions at the different waveguide edges of the 2D waveguides.
