Quantifying the Effect of Ethanol Content, Activation Energy, Key Radicals on Laminar Combustion Characteristics of Premixed Gas Through Experiments and Numericalanalysis

To better achieve the goal of carbon neutrality, blending ethanol with hydrogen has become a research hotspot. In this essay, the effects of ethanol addition on the fuels of Hydrogen methane mixing fuel were discussed. The laminar combustion characteristics of ethanol/hydrogen/methane mixture under different ethanol content, pressure (1 bar, 2 bar), and equivalence ratios (0.7~1.4) were experimentally and numerically simulated. The research results had shown that as ethanol addition increased, the laminar combustion rate of the premixed gas slowly shrinks, and the peak laminar burning velocity also shifted towards higher equivalence ratios as the ethanol blending ratio increased, which will make the premixed fuel tend to stabilize. The laminar combustion velocity and ethanol blending ratio were proposed as the formula to analyze, the error was very small. Fitting equations for activation energy, ethanol concentration, and equivalence ratio, the fitting accuracy was very high. The key elementary reaction was obtained through numerical simulation, and the relationship between free radicals and laminar combustion speed was quantified, it was found that the strongest correlation was found between OH radicals and the laminar flame velocity in lean-fuel condition, during rich combustion, the correlation between H radicals and laminar flame velocity was strongest.