Large eddy simulation based on an improved high-precision interior penalty discontinuous Galerkin method: flow past cylinders and airfoils

The accuracy of flow field prediction relies on the resolution of the flow structures, and numerical simulation of flow field based on high-precision methods is of great significance. To this end, an improved interior penalty discontinuous Galerkin (IPDG) method was adopted in the present study to conduct large eddy simulation (LES). It has been validated that the improved IPDG method can reach a precision of at least fourth order. Moreover, the effects of subgrid-scale models and numerical dissipation in the IPDG-LES framework remain questionable. Therefore, the turbulent flow past a circular cylinder at Re = 3900 has been systematically investigated. Compared with Smagorinsky models with/without a damping function and wall-adapting local eddy viscosity model, the dynamic subgrid model leads to higher accuracy due to the modeling strategy. The effect of numerical dissipation seems perverse, and the discrepancy could be attribute to the generation of aliasing error and resolved viscosity when numerical dissipation is artificially suppressed. In addition, NACA0021 airfoil flow simulation at AOA = 60 deg and Re = 2.7 × 10⁵ has been conducted. The characteristics of the turbulence field and high precision are also well demonstrated under the IPDG-LES framework.