Laminar flame characteristcs of ethanol-air mixture: Experimental and simulation study

Experimental test for laminar combustion of ethanol-air mixture was investigated in a constant volume combustion bomb. The laminar burning velocity and Markstein length were determined over an extensive range of equivalence ratios from 0.7-1.6 under an initial condition of 0.1 MPa pressure and 358 K temperature, with high-speed Schlieren system. The methods of linear extrapolation and non-linear extrapolation are compared and discussed. Apart from experiments, simulation was carried out in Chemkin by using the Marinov ethanol oxidation mechanism. Results indicate that non-linear extrapolation is more suitable to calculate the laminar burning velocity of ethanol-air mixture. The overall trends of laminar burning velocity vs. equivalence ratio are consistent between the experiment and simulation. The peak values of the laminar burning velocity from present experiment and simulation are 531.2 mm/s and 565.3 mm/s, both appearing at the equivalence ratio of 1.1. Moreover, the Markstein length of ethanol-air mixtures generally decreases with increasing equivalence ratio