@inproceedings{2019-00110, title={Lagrangian-Lagrangian Modelling of an N-heptane Jet at Diesel Engine Conditions}, booktitle={18th Australasian Fluid Mechanics Conference}, year={2012}, month={dec}, author={Y. Pei and E.R. Hawkes and S. Kook}, abstract={The composition Probability Density Function (PDF) model is coupled with a standard Reynolds-averaged k − ε turbulence model and a reduced chemical mechanism to simulate transient n-heptane spray injection and ignition in a high temperature and high density ambient fluid. The molecular diffusion is modelled by a Modified Curl (MC) mixing model. The liquid phase is solved by a Discrete Phase Model (DPM). This represents the first application of the Lagrangian-Particle Lagrangian-Fluid (LPLE) implementation of the PDF method applied to practical diesel engine conditions. A non-reacting case was first considered, with the focus on the ability of the model to capture the spray structure, e.g., vapour penetration and liquid length, fuel mixture fraction and its variance. The predictions of liftoff length and ignition delay for reacting cases were then compared to experiment and to a set of results from a well-mixed model that ignores turbulence-chemistry interactions, which is the de facto standard for diesel engine modelling today. Significant structural differences in the modelled flame are revealed comparing the PDF method with the well-mixed model. Quantitatively, the PDF model performs better than the well-mixed model in most cases.} }