APPLICATION OF REYNOLDS STRESS MODELING TO ENGINE FLOW CALCULATIONS

To improve the prediction of turbulence inside internal combustion eng ines, a Reynolds stress turbulence model is implemented in the Kiva-II code. After a rapid description of the Launder-Reece-Rodi model (note d LRR), two validation test cases (the plane channel flow and the flow over a backward facing step) are presented. The advantages of a secon d order closure and the shortcomings of the LRR model are then analyze d. Finally, a simulation of an intake and compression stroke using bot h the standard k-epsilon model and the LRR model is described. As a pr ecise knowledge of the velocity and turbulent fields near TDC is neces sary for the prediction of the mixing and the combustion processes, we have analyzed the influence of the turbulence model on the flow field . Results are compared with experimental data and show a strong influe nce of the turbulence model even on the mean flow, especially at the e nd of the compression stroke (TDC).