Far field behaviour of waves in a vibrationally relaxing gas

In this paper an asymptotic method is used to derive an evolutive equation which governs an unsteady planar or radially symmetric flow of a vibrationally relaxing gas in the far field. Numerical solutions are presented using a recent method after incorporating certain modifications; the results highlight the various effects of nonlinearity, relaxation and geometrical spreading. (C) 2002 IMACS.