A study of the effect of hydrogen on methane deflagration characteristics in a square confined space

Abstract

Macroscopic and microscopic explosion kinetic properties of H2/CH4/air mixtures are investigated. The explosion characteristics of CH4/air mixtures with different hydrogen blending ratios(0–25%) are investigated experimentally. It is found that the increase of hydrogen blending ratios has almost no effect on the peak overpressure of the methane gas explosion, but the rate of maximum pressure rise, the explosion index and the flame propagation velocity increase significantly. The effect of hydrogen blending ratios on the chemical kinetics of CH4-air mixtures is analyzed based on the CHEMKIN software. The concentration of key radicals, which play a major role in the reaction, does not change much as the hydrogen blending ratio increases. A prediction model of explosion overpressure in a square confined space is established using the segmentation method, and it is verified that the relative errors between the model calculation results and experimental results are less than 10%.