Development of a Numerical Model for Investigating the EDI+GPI Engine

摘要

This paper reports the development of a CFD model for investigating the ethanol direct injection plus gasoline port injection (EDI+GPI) engine. The model was developed using the commercial CFD code ANSYS FLUENT as a solver. The computational domain was meshed based on the scanned geometry of the cylinder head. Realizable k-ε turbulence model was used to simulate the in-cylinder flows. The Eulerian-Lagrangian approach was used to model the evolution of the fuel sprays. The dual-fuel combustion process was modelled by the Extended Coherent Flame Model (ECFM) in the partially premixed combustion concept. A five-dimensional presumed Probability Density Function (PDF) look-up table was used to model the dual-fuel turbulence-chemistry interactions. The model was verified by the good agreement between the numerical and experimental results of spray shapes in a constant volume chamber and cylinder pressure on the EDI+GPI research engine. Sample simulation results showed that the model was capable to simulate the spray combustion process of the EDI+GPI engine and meet the needs of the investigation.