Application of the Cross-Sectional Average Method to Calculations of the Dense Spray Region in a Diesel Engine

An interactive approach to Diesel spray simulation is proposed in which a one-dimensional cross-sectionally averaged system of equations for the two-phase flow is solved independently of the CFD-code in order to provide the source terms accounting for the mass, momentum and heat exchanges between the gas and liquid phase. The transport equations are solved in the multi-dimensional CFD-code only for the gas phase. Validation is performed by comparing the computed spray penetration lengths and the distribution of fuel mass fraction to experimental data and with the computational results of KIVA-II. The computational results agree well with the measurements and are shown to be grid-independent, while the spray model in KIVA-II leads to a strongly grid-dependent result.