Journal Article
A Numerical Study of the Effect of EGR on Flame Lift-off in n-Heptane Sprays Using a Novel PaSR Model Implemented in OpenFOAM
2012-04-16
2012-01-0153
The effect of exhaust gas recirculation (EGR) on flame lift-off in non-stationary n-heptane sprays was studied under Diesel engine-like conditions using numerical simulation involving complex chemistry and a novel partially stirred reactor (PaSR) model of subgrid turbulence-chemistry interaction. The flame-stabilization mechanism is a result of complex physical and chemical interactions and cannot be described by a simplified theory. To leading order it is determined by the chemical reaction time at the leading edge, the turbulent diffusivity, and the flow velocity; so that there exists a balance between the local convection velocity and the triple-flame propagation speed. In this study of ignition and flame formation and stabilization processes, the VSB2 stochastic blob-and-bubble spray model was used in combination with the volume reactor fraction model (VRFM) implemented in OpenFOAM.
