An approach for including evaporation in a model for predicting spray penetration
Conferece paper presented at ILASS-Asia 2016, 18th Annual Conference on Liquid Atomization and Spray Systems - Asia, Chennai, India
One of the key topic of research in the field of Internal Combustion engines has been fuel sprays as it is a major determinant in the efficiency and hence the performance of the engines. But because of the complexity of the physics involved and the number of parameters that affect the spray, it is fairly tasking to deduce an exhaustively descriptive model of spray mechanics.
These difficulties include unsteady in-chamber conditions, phase change in the spray and the internal flow in the injector. Nevertheless, many models with modest assumptions have been proposed, which reasonably capture the physics of fuel spray. Only a handful of papers have taken the approach of fuel being considered as isolated droplets travelling in the spray and subsequently undergoing evaporation effects. In many studies the effect of evaporation is neglected since they assume that it is negligible.
We adopt an earlier model based on differential control volume analysis for the mass and momentum conservation of fuel and entrained ambient gas, and extend it to account for the evaporation of the droplet. The mechanics of fuel spray is examined by focusing our study on the changes in the temporal evolution of the fuel spray. This study on Hexane fuel spray shows us that evaporation indeed has an effect on the spray dynamics and cannot be outright neglected.