Effects of mesh density on LES of the flow structure in internal combustion engine

Abstract

By using the software FIRE, the flow structure of 186FA diesel engine were analyzed by numerical simulation. The indicator diagram, velocity field and turbulent kinetic energy in the cylinder were simulated by both the k-ε model and the large-eddy simulation(LES) model. The results shows that the mesh density has little effect on the flow structure when the k-ε model is adopted. Compared with the k-ε model, the LES model shows a significantly different and relatively more complex turbulence structure，and its turbulent kinetic energy is much lower than that of the latter. At the same time, the finer the mesh is, the more distinct the effect is.