Large Eddy Simulation with Sub-grid Stress Determined by Molecular Simulation and its Applications for Turbulent Channel Flows

In this paper, a novel simulation method of turbulence by solving filtered Navier-Stokes equations based on LES methodology and calculating the sub-grid scale stress with D-IP method is developed. Compared to the sub-grid scale models used in LES method with Boussinesq assumption, the sub-gird scale stress of the LES-DIP method is directly estimated based on statistics of molecule motions. To validate the LES-DIP method, turbulent channel flow at different Reynolds numbers of Rer=180, 390 and 590 are simulated. The results are found to be in agreement with those of DNS with much smaller computational cost.