Large-eddy simulation of in-cylinder flows

Advances in physical models, numerical methods, and computational power tog ether have brought large-eddy simulation (LES) to the point where it warran ts serious consideration for computing in-cylinder turbulent flows. This ar ticle includes: a discussion of LES and how it differs from Reynolds-averag ed Navier Stokes (RANS) modeling; motivation for transitioning to LES for i n-cylinder flow in IC engines; and quantitative results for two motored eng ine configurations. "Dynamic" sub-grid-scale stress models are emphasized, and results from two different numerical approaches are discussed. Compared to RANS, LES requires a low level of empirical input, provides more comple te information on in-cylinder flow structure, and makes previously inaccess ible phenomena (e.g., cycle-to-cycle variability) amenable to analysis.