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This study demonstrates the use of Tabkin® to model auto-ignition, development and stabilization of a lifted n-heptane spray flame. An advanced combustion named Dacolt PSR+PDF model has been implemented in ANSYS® FLUENT®. This model is a mixture fraction/progress variable approach with presumed Probability Density Function (PDF) modeling of turbulence-chemistry interactions. N-heptane is used as a model fuel and a detailed chemical-kinetic mechanism is used to model the combustion chemistry. Tabkin is used to generate the look-up table for the Dacolt PSR+PDF combustion model. The results show that the basic physics of a lifted diesel spray flame, namely auto-ignition, flame development and flame stabilization, are well captured by the mixture fraction/progress variable modeling approach. Also, it is demonstrated that the working cycle of using an advanced combustion model with a complex chemistry look-up table is greatly simplified with the use of Tabkin.

Diesel combustion is a very complex process, involving a reacting, turbulent and multi-phase flow. Furthermore, heavy duty engines operate mainly at medium and high loads, where injection durations are very long and cylinder pressure is high. Within such context, proper CFD tools are necessary to predict mixing controlled combustion, heat transfer and, eventually, flame wall interaction which might result from long injection durations and high injection pressures. In particular, detailed chemistry seems to be necessary to estimate correctly ignition under a wide range of operating conditions and formation of rich combustion products which might lead to soot formation. This work is dedicated to the identification of suitable methodologies to predict combustion in heavy-duty diesel engines using detailed chemistry.