Effect of ethane concentration on burning velocity and flame stability of nature gas and coalbed gas

In this paper, combustion characteristics of premixed methane-ethane-air mixtures with various ethane concentration at different equivalence ratio under elevated pressure and temperature (p=0.75 MPa, T=450 K) will be reported. The effect of ethane concentration on burning speed and flame stability will be discussed. Experimental results show that with the increase of ethane concentration the unstretched burning velocity is increased. The Markstein length is increased as well, which shows that the flame stability is enhanced. Within the range of this study, unstretched flame speed and unstretched burning velocity are increased until reaching the peak value and then reduced with the increase of equivalence ratio. The maximum value is obtained near the stoichiometric ratio.