AN IMPROVED MODEL FOR PREDICTING EVAPORATION OF HIGH PRESSURE ENGINE SPRAYS

A comprehensive evaporation model is proposed for spray applications under high temperatures and pressures. The model includes the effects of Stefan flow on heat and mass transfer rates. Internal circulation is accounted using the effective conductivity model of Abramzon and Sirignano [1]. Equilibrium composition at high pressures is calculated using a real gas equation of state. Properties are evaluated as functions of temperature, pressure and composition. The proposed evaporation model is implemented in the KIVA code [2] and simulation predictions are compared against the experimental data of Suzuki et al. [3] for an α-methylnapthalene spray injected in a chamber pressurized with nitrogen gas. Using the proposed evaporation model, predictions of fuel vapor distribution are in improved agreement with measurements compared to the original KIVA evaporation model.