Numerical diffusion based on high-order derivatives in MUSCL schemes for LES on unstructured grids

A MUSCL scheme in which stabilization is obtained through numerical diffusion based on sixth-order derivatives is presented. Such a dissipation has a very localized effect on high frequencies and, thus, the interaction with SGS modeling should be reduced. Moreover, a key coefficient permits to tune the numerical dissipation to the minimum amount required to obtain stable calculations. The proposed approach is applied to the large-eddy simulation of the flow around a square cylinder on an unstructured grid. Results are compared with experimental and LES data in the literature and with the results obtained in previous simulations carried out with upwinding based on fourth-order derivatives.