Application of a New 1D Combustion Model to Gasoline Transient Engine Operation

The reduction of pollutant emissions and fuel consumption of a car, while maintaining its driveability, is one of the major goals of car manufacturers. The engine control seems to be a promising solution for this issue. Indeed, it is based on the optimisation of the engine operating conditions. Its development is made under engine transient operations, using experimental test-beds or numerical simulations. This last method requires however complex and sophisticated 1D system simulation software, due to the dynamic interactions between all the engine sub-systems.

This paper presents the interest of using a 1D physical combustion model for gasoline transient engine applications instead of traditional empirical models. The proposed model, called CFM-1D, is based on the 3D gasoline combustion model ECFM [1]. In this model, the combustion chamber is divided into two zones: the burned and unburned gases. These 2 zones are separated by a premixed turbulent flame, which is modelled using a 1D adaptation of the 3D flame surface density approach [1]. This combustion model is validated comparing 1D and 3D results on an engine steady state operating condition. Then, using experimental results, a validation on a wide range of engine steady state conditions is performed. Finally, an application to a transient simulation of a turbo-charged gasoline direct injection engine is proposed to demonstrate the validity of this approach.