Direct-Injection Stratified-Charge Engine Computations With Improved Submodels for Turbulence and Wall Heat Transfer

Compared to results in a previous publication by this author, new computations using more realistic submodels (logarithmic law-of-the-wall) for wall heat transfer and wall shear stresses showed better agreement with experimental data from a DISC (Direct-Injection Stratified-Charge) engine. The computation preserved the good agreement in measured trends of the HC and NO emissions which was observed in the previous results. The effects of the improved submodels (logarithmic law-of-the-wall and k-ε turbulence model) on the computed fluid-flow field and combustion are discussed.