Large eddy simulation of mixing layer

摘要

Large eddy simulation (LES) of spatially evolving turbulent mixing layer is carried out in this paper. The predicted evolution of large vortex structures agrees well with the experimental visualization results. The linear growth of momentum thickness along the streamwise direction is obtained, indicating that the pairing and amalgamating of large vortex structures in plane mixing layers occurs randomly in time and space. Self-similarity property of mixing layer is also obtained, which agrees with many experimental discoveries. The mean properties including streamwise velocity, fluctuating velocities and Reynolds shear stress agree well with experimental measurements quantitatively. It shows that LES can achieve accurate quantitative simulation as well as a reasonable vortex structure of mixing layer.