A Study of Flame-Vortex Interactions in the Presence of Residual Gases

In this work the effects of residual combustion products from a prior injection on flame extinction characteristics in a Diesel fuel pulse are investigated through a fundamental study. A numerical code with sixth-order accurate spatial discretization and multiple-step chemical kinetics is used to simulate flame-vortex interactions under Diesel conditions in the presence of residual combustion product mixtures. The results indicate that there is a balance between the heating effect of the high-temperature combustion products that enhance flame stability and the dilution effect of the reduced oxygen concentration, which promotes extinction. These counteracting aspects of the entrained combustion products can lead to an ideal dwell time between multiple injection events for optimum benefits in flame stability.