The asymptotic solution of the unsteady planar parallel gas flow for the case that the adiabatic index number γ is big

In ref. l. under the condition that the components of velocity are only the functions of time and polar angle 0. Dvornikov solved eqs. (1.1)–(1.3) of the ideal gas unsteady planar parallel potential flow. It was pointed out in ref.[1] that in general cases, the evident solutions could not be obtained. Only for two especial cases, the evident solutions were obtained. In this paper, the author studies the same problem as that in ref. [1]. In the first section we obtain the evident solution of equations (1.1)–(1.3) under the condition that the sonic velocity is restricted by some complemental conditions. In the second section, we obtain the first-order approximate solutions of the fundamental equation for the case that