Constants of ignition delay model of diesel fuel surrogates with cetane numbers of 35 and 45, based on Cantera simulations

Abstract

The study aims to present new constants of ignition delay based on the Arrhenius model for two diesel fuel surrogates formulated from four components (n-Hexadecane, Heptamethylnonane, Decahydro-naphthalene, and 1-Methyl-naphthalene) as a function of temperature and pressure, obtained by simulation in an adiabatic, homogeneous and constant pressure reactor using the Cantera simulator. The reaction was considered stoichiometric, with a temperature and pressure range varying from 700 to 2200 K and 40 to 120 atm, typical values found in the combustion chamber of turbocharged compression ignition engines. It was found that two-stage combustion occurs for temperatures between 700 and 1000 K (for pressure of 80 atm). When the combustion occurs in two-stages, we detail the ignition delay of each stage, and its first-stage fraction are presented. Surrogate fuels was modeled in 35 and 45 cetane numbers and 48 and 35 threshold soot index, respectively, to compare low and medium fuels in cetane numbers. The main application of these models relates to stochastic combustion models, which require fast models with low computational cost. The main differential of this study refers to its description of two-stage combustion, if it occurs. The model does not consider the physical ignition delay, referring to atomization, mixing and heating of the fuel. Results were compared with models from the literature, showing good agreement and presented intermediate values when compared with the literature.