The temperature dependence of the laminar burning velocities of methyl formate + air flames

Abstract

Laminar burning velocities, SL, of methyl formate and air flames were determined at atmospheric pressure and initial gas temperatures, T, of 298, 318, 338 and 348 K. Measurements were performed in non-stretched flames, stabilized on a perforated plate burner at adiabatic conditions, generated using the heat flux method. These new experimental data shed light on discrepancies seen in previously published results, and the temperature dependence of the laminar burning velocity of methyl formate was analysed using expression SL = SL0(T/T0)α. It was found that the power exponent, α, has a minimum close to equivalence ratio, ϕ, of 1.0. Both the laminar burning velocities and alpha coefficient were compared with predictions of the mechanisms of Glaude et al. (2005), Dooley et al. (2010) and Dievart et al. (2013). While the two latter mechanisms are in generally good agreement in lean mixtures, the Glaude mechanism over predicts the experimental burning velocities over the entire range of equivalence ratios. The temperature dependences predicted by the Glaude and Dievart mechanisms, however, are rather close and agree well with the measurements. To elucidate these differences and similarities in the performance of two mechanisms, the sensitivity analysis of the power exponent α was performed for the first time. It was demonstrated that examination of the temperature dependence of the burning velocity provides an independent approach for analysis of experimental data consistency.