Combustion chemistry in premixed C2F4---O2 flames

The flame speed and combustion product distribution in a premixed C2F4---O2 flame at atmospheric pressure have been measured and are compared with computational predictions. The dependence of the flame speed on fuel/oxygen ratio compares well with previous measurements. In contrast to hydrocarbon flames, the flame speed does not correlate with the adiabatic flame temperature, i.e., the maximum flame speed does not occur at the composition corresponding to the maximum adiabatic flame temperature. COF2 is observed to be the predominant combustion product for all fuel concentrations. The relative amounts of products experimentally observed are not in accord with those predicted by thermodynamic calculations. The previously published chemical mechanism derived from shock tube data is not adequate to explain our experimental results. An improved chemical combustion mechanism is proposed and tested using modern chemical kinetic computational codes. Suggestions are made for experiments to validate and improve the proposed mechanism.