Inherent instabilities in ethyl acetate premixed flames

The intrinsic flame instability of ethyl acetate (ETAC) spherically expanding premixture flame has been investigated and discussed using experimental and theoretical analysis at the initial temperature and pressure of 358 K, 388 K, 418 K and 1 bar, 2 bar, and 4 bar as well as the equivalence ratio of 0.8-1.6 using the constant volume combustion chamber (CVCC). When a premixture flame becomes unstable and cellularized the flame surface is wrinkled which further facilitates the rapid accelerative motion of the flame. Considering this, the wrinkling factor of the premixture was assessed. It was revealed that the wrinkling factor increases as the Peclet number increases. Comparative analysis of the experimental and theoretical Peclet number showed that the experimental data was smaller than the theoretical data, however, their trend was consistent. Flame instability was also investigated using the critical Peclet number (Pe(c)) and the Markstein number (M-b) and empirical correlation Pe(c) = 52.31M(b) + 260.43was attained. In conclusion, an empirical correlation Ka(c) = 0.04704e((-0.33466Mb)) and Ka(cl) = 0.04959e((-0.25775Mb)) was established in terms of the Karlovitz numbers (Ka) and the Markstein number (M-b).

Automated summary

The intrinsic flame instability of ethyl acetate spherically expanding premixture flame was investigated using experimental and theoretical analysis. The wrinkling factor of the premixture was found to increase with the Peclet number. Experimental data showed smaller Peclet numbers compared to theoretical, although the trend was consistent. An empirical correlation between flame instability and Markstein number was established.