FAR-FIELD BEHAVIOR OF WAVES IN A RELAXING GAS

An asymptotic equation is derived which describes the far-field behavi or of the governing system of partial differential equations for a one dimensional unsteady plane and radially symmetric Bow of an inviscid relaxing gas; this evolution equation, is a generalized Burger's equat ion, which enables us to study in detail the various effects that appe ar in the propagation of plane, cylindrical and spherical waves in a d issipative medium with a quadratic nonlinearity. An approximate soluti on of this equation is obtained by using the method of matched asympto tic expansions; the method enables us to determine how the shock ampli tude and the shift in the shock center are influenced by the relaxatio n effects. (C) 1997 Elsevier Science Ltd.