Laminar flame structure of ethyl pentanoate at low and atmospheric-pressure: Experimental and kinetic modeling study

Ethyl pentanoate (EPE) or ethyl valerate is considered a surrogate for biodiesel fuels and a potential fuel for spark ignition engines. Knowledge of its combustion chemistry is of great importance for the development of high-performance and environmentally friendly combustion devices fueled with biofuels. In this work, a detailed chemical kinetic mechanism for the combustion of EPE is developed on the basis of a well-validated kinetic model proposed earlier for short ethyl esters up to ethyl propionate (by Sun et al.). The Sun et al. mechanism was augmented with primary oxidation reactions of ethyl butanoate and ethyl pentanoate and specific intermediates involved in these reactions. The proposed kinetic mechanism was validated against the new experimental data reported in this work on the chemical speciation of laminar premixed flames of stoichiometric EPE/O2/Ar mixtures at low (50 Torr) and atmospheric pressures. The mechanism provided a good predictive capability for experimental mole fraction profiles of many flame intermediates. The new mechanism was also shown to predict well literature experimental data on laminar flame speeds of EPE/air mixtures in a range of equivalence ratios and pressures. The reported flame data can be used for validation of kinetic models for ethyl ester-based biofuels.