Application of large eddy simulation to a diesel spray

Large eddy simulation (LES) is applied to the numerical computation of a diesel spray in a constant volume vessel. Computational results are compared with those obtained by a RANS (RNG k-Ε) model as well as with experimental data. The effects of the mesh grid density are examined. The results show that the spray penetration calculated by LES is decreased with refined mesh, while the prediction by RANS is almost independent of the mesh density. Meanwhile, the Sauter mean diameters obtained by both models are insensitive to the mesh. LES provides better agreement in spray characteristics compared with RANS. Moreover, random micro structure of the turbulent fuel spray can be trapped by LES, and precisely predicts the turbulent characteristics.