Assessment of Applicability of Auto-Generated Grid in Large Eddy Simulation of Flow Around a Cylinder

Abstract:

To assess the applicability of an auto-generated grid system named snappyHexMesh grid in large eddy simulation， the simulation results of the flow around a circular cylinder at an Re of 3 900 and a square cylinder at an Re of 22 000 based on both the snappyHexMesh grid system and the artificial grid system were compared in this paper. By configuring suitable computational domains and setting proper numerical schemes， both the snappyHexMesh grid and the artificial grid system show good numerical stability during each simulation process. The comparison of the numerical results using different grid systems with the experimental data shows that using the snappyHexMesh grid can enhance the numerical efficiency； the flow around a circular cylinder is sensitive to the change of the grid system， and the snappyHexMesh grid with different densities will significantly affect the aerodynamic characteristics and the flow structures in the wake of a circular cylinder； the flow around a square cylinder can be accurately reproduced using snappyHexMesh grid system， and the snappyHexMesh grid system has a better applicability in large eddy simulation of the flow around a square cylinder than that of a circular cylinder.