A global combustion model for simulation of n-heptane and iso-octane self ignition

For CFD-simulations, superposed with combustion phenomena, simplified reaction models are needed to reduce calculation times. In the present study, a global kinetic model for gasoline fuels was developed, whereby the focus was on the simulation of self ignition and estimation of main off-gas components (CO2, H2O, CO and H2). The developed reaction system, consisting of 18 species (8 molecules, 10 species classes) and 19 mostly global reactions was validated for T = 600–1250 K and for p = 13–40 bars for equivalence ratios of Φ = 0.5 to Φ = 2 for combustion simulation of iso-octane, n-heptane and mixtures of both. Simulated ignition delay times were compared to shock-tube data and validated by a detailed combustion mechanism; these were then compared to approved reduced mechanisms. Species histories of different ideal reactor simulations were compared to literature data and detailed simulation results.

► Development of a global model for gasoline fuel combustion simulation. ► Simulation of self ignition of iso-octane and n-heptane surrogates. ► Ignition delay time and species histories validation. ► Simulation of HCCI engines.