Development of a Reduced TPRF-E (Heptane/Isooctane/Toluene/Ethanol) Gasoline Surrogate Model for Computational Fluid Dynamic Applications in Engine Combustion and Sprays

Abstract

Investigating combustion characteristics of oxygenated gasoline and gasoline blended ethanol is a subject of recent interest. The non-linearity in the interaction of fuel components in the oxygenated gasoline can be studied by developing chemical kinetics of relevant surrogate of fewer components. This work proposes a new reduced four-component (isooctane, heptane, toluene, and ethanol) oxygenated gasoline surrogate mechanism consisting of 67 species and 325 reactions, applicable for dynamic CFD applications in engine combustion and sprays. The model introduces the addition of eight C1-C3 species into the previous model (Li et al; 2019) followed by extensive tuning of reaction rate constants of C7 - C8 chemistry. The current mechanism delivers excellent prediction capabilities in comprehensive combustion applications with an improved performance in lean conditions. The mechanism has been applied to validate the measured data across a wide range of temperature, pressure, equivalence ratio (f), and RON ranges. In addition to Ignition delay times (IDT) and Flame speed (FS), the model is used to validate species concentration analysis in the premixed flames and flow reactor as well as on coupling with CFD. The model is also used to validate HCCI combustion of PRF and TPRF mixtures in CFR engine and the reactive spray simulations for n-heptane and PRF's in constant volume chamber Spray A simulations according to ECN recommendations.