Scaling law of resolved-scale isotropic turbulence

In large-eddy simulation (LES), EDQNM theory is employed to calculate the scaling laws of second- and third-order structure functions, and the skewness of velocity increment, in resolved-scale isotropic turbulence with three different filters, respectively. The scaling law and skewness are affected by several factors, such as the ratio of two-point distance to filter size, the LES Reynolds number, and the type of filter. Results show that, when two-point distance is the same magnitude as filter size, or LES Reynolds number is small, both the scaling law and skewness of resolved-scale turbulence are far from those of full-scale turbulence and should be corrected. Three examples of subgrid modeling using these results are then introduced.