The effects of the mixing of ethane and propane on the ignition delay time of methane were studied through the shock tube and CHEMKIN software.The cause of these effects was analyzed from the perspective of chemical kinetics. The results show that the addition of ethane and propane can shorten the delay time of methane ignition

but this influence becomes smaller along with the increase of temperature. The sensitivity analysis suggests that H + O2=O + OH (R1) promotes ignition most both for the mixture fuels of methane/ethane and methane/propane

and the two elementary reactions of CH4 + H=CH3 + H2 (R128) and CH4 + OH=CH3 + H2O (R129) exert maximum inhibition for the ignition of methane/ethane and methane/propane blends. It is found that the increase of the ratio of ethane and propane in the mixed fuels of methane/ethane and methane/propane has little influence on the main reaction path of methane

but mainly affects the consumption rate of CH3.