Reduced model of chemical kinetic and two-dimensional structure of detonation wave in rich mixtures of methane with oxidizer

Abstract

Two-step reduced model of chemical kinetics of detonation combustion of methane mixtures is presented. The possibility of condensed carbon (soot) microparticles formation in reaction products is taken into account for the first time. The model is simple (only one ordinary differential equation in a main heat release zone) and physically grounded. It is in consistent with the second law of thermodynamics and Le Chatelier’s principle. The model verification has been performed via numerical calculations of parameters and two-dimensional structure of detonation wave in the fuel-rich methane-oxidizer mixture. The irregular cellular structure of the wave with all its main features, observed in the experiments, was reproduced in the calculations. The dominant size of the detonation cell is in good agreement with experimental data and corresponding estimations in the frames of generally accepted Vasil’ev-Nikolaev model of detonation cell.