Turbulent combustion modeling for internal combustion engine CFD: A review

The modeling of combustion or, to be exact, turbulent combustion using numerical simulation has become state-of-the-art in the process of developing internal combustion engines (ICE). Since the combustion regimes that occur fundamentally differ depending on the combustion concept used, several turbulent combustion models have been developed to meet the respective requirements. The selection of appropriate combustion models is crucial to accurately reflect the physical processes, specifically considering the mixing conditions and the effects of turbulence on the mean reaction rate. This review provides an overview of turbulent combustion models for use in ICE computational fluid dynamics. After a brief introduction to the basic aspects of ICE combustion simulation, the underlying governing equations and the required physical background are outlined. Next, the relevant turbulent combustion models for ICE application and their mathematical formulations are aggregated to enable the discussion of relevant model parameters and characteristics. A comprehensive review of application cases with respect to ICE technologies, namely spark ignition and compression ignition, is given. Furthermore, recent advances and future prospects in terms of the integration of future fuels, the enhancement of turbulent combustion models to meet future engine technologies and the use of machine learning techniques to advance turbulent combustion simulation in the context of ICE are discussed.