Passage of a shock wave through a region with temperature or concentration inhomogeneities

Measurements have been made on the motion of a shock wave in a hot gas at constant pressure; differential relationships have been derived for the one-dimensional motion in a perfect gas in which the temperature and velocity are dependent on a coordinate; other results have been obtained for a gas mixture having a distribution of the component concentrations at constant pressure and temperature. Formulas are given for the time derivative of the Mach number of the wave and the derivative of the density with respect to the coordinate in the gas behind the wave for the instant when the wave encounters the boundary of the nonuniformity. Results are given from numerical calculations on the passage of a shock wave through a gas with a negative density gradient at constant pressure. The theoretical values for the change in shock-wave speed are compared with the measured ones.