Development and Validation of a Reduced N-Heptane/Toluene/DMF-PAH Mechanism for Diesel Engine Application

Abstract

The application of 2,5-dimethylfuran (DMF) as an alternative fuel for internal combustion engines has been gaining popularity. In the present study, a reduced n-heptane/toluene/DMF-polycyclic aromatic hydrocarbon (PAH) reaction mechanism contains 94 species amongst 249 reactions has been proposed and applied to simulate the combustion process of diesel engine fueled with diesel and DMF. First, a detailed reaction mechanism for DMF from the literature was chosen and reduced using combined mechanism reduction methods under engine-relevant conditions. Second, the reduced mechanism of DMF was optimized and incorporated into an existing reduced n-heptane/toluene-PAH mechanism to form a three-component chemistry mechanism, consisting of n-heptane, toluene and DMF. Third, the combined mechanism was further reduced and its predictive capability was improved by adjusting the rate constants of selected gas-phase reactions. Subsequently, the proposed three-component mechanism was compared and validated with experimental measurements of ignition delay times, species mole fractions and laminar burning velocities acquired from published papers. Finally, new diesel engine experiments were conducted and have also been used to evaluate the developed mechanism. Overall, the predicted results obtained by this proposed n-heptane/toluene/DMF-PAH mechanism are in reasonable agreement with the available experiments.