APPLICATION OF THE DETAILED REACTION MECHANISM OF FUEL OXIDATION FOR MODELING MULTISTAGE AUTOIGNITION IN DIESEL ENGINE

Three-dimensional (3D) numerical simulations of mixture formation, autoignition, and combustion processes in a cylinder of Diesel engine using the detailed reaction mechanism (DRM) of fuel oxidation (liquid n-tetradecane and liquid surrogate fuel containing 56%(wt.) n-hexadecane and 44%(wt.) toluene) are performed. Special attention is paid to the autoignition process. Calculations show that despite the high in-cylinder temperature before the start of fuel injection (∼ 1100 K), the autoignition of fuel spray has a staged nature with cool and blue §ames followed by hot explosion. The in§uence of the numerical time step and spatial resolution of the exothermic centers on the multistage autoignition is investigated. It has been established that for the correct modeling of the autoignition delay, both the integration time step and spatial resolution must be varied in such a way