Calculation of stationary subsonic flows of chemically non-equilibrium gas mixtures in channels with variable cross sections under conditions of arbitrary finite changes in density

An effective method for numerical simulation of essentially subsonic stationary flows of chemically non-equilibrium gaseous mixtures in plane and axisymmetric channels with variable cross sections in the presence of arbitrary finite changes in the flow density is described. The method is based on application of an ultimate form of the complete system of Navie-Stocks equations for chemically reacting gas mixture corresponding to the Mach number tendency to zero. Numerical integration of this system is realized by means of an economical pelaxation algorithm based on introduction of artificial compressibility and employing the principle of disintegrating the initial system of equations by spatial directions and physical processes. Results of calculating the flow of dissociating nitrogen dioxide in heated axisymmetric channels of constant and variable (with a sudden expansion) cross sections are given as an example of using the suggested method. A possibility is discussed of applying a narrow channel approximation for description of the flows being considered