Gas-Dynamic Stabilization and Intensification of the Methane Oxidation Macrokinetic Processes in the High-Enthalpy Oxygen-Containing Flow

The paper presents experimental results of studying the macrokinetic intensification and stabilization processes of methane oxidation (combustion) in the high-enthalpy oxygen-containing flow inside the constant cross section channel being finite along its length. Calculation and experimental data are presented on the methane oxidation gas-dynamic intensification and stabilization in the recirculation zone of the high-enthalpy oxygen-containing flow formed behind the wedge-shaped bluff body. Computational and experimental studies enabled to consider various configurations of the bluff bodies differing in their number and degree of the constant cross section channel obstruction. Dependence of the gas relative residence time in the recirculation zone behind the bluff bodies was determined for various configurations. Range of the initial enthalpy values of the high-enthalpy oxygen-containing flow of 350--700 kJ/kg was considered. Regularities were established for the influence of the flow obstruction degree on the physical and chemical processes completion in the channel under study. Methane oxidation intensity in the high-enthalpy oxygen-containing flow was compared with and without the gas-dynamic stabilization. The level of lower limit value of the fuel excess coefficient corresponding to the stable methane ignition and combustion was determined. The data obtained indicate intensification in the methane oxidation diffusion-kinetic regimes and make it possible to evaluate the factors that are limiting completion of the physical and chemical processes