A challenging test case for large eddy simulation: high Reynolds number circular cylinder flow

A thorough numerical investigation of high Reynolds number (Re=140,000) circular cylinder flow was performed based on large eddy simulation (LES). The objective was to evaluate the applicability of LES for practically relevant high-Re flows and to investigate the influence of subgrid scale modeling and grid resolution on the quality of the predicted results. Because the turbulent von Kármán vortex street past circular cylinders involves most of the characteristic features of technical applications, it is an ideal test case for this purpose. Based on a parallelized finite-volume Navier–Stokes solver, computations were carried out on a series of grids applying both the Smagorinsky and the dynamic subgrid scale model. The simulations yielded information on the time-averaged flow field, the resolved Reynolds stresses and integral parameters such as drag coefficient, recirculation length and Strouhal number. The results were analyzed in detail and compared with experimental data. In general, the LES results agreed fairly well with the experimental data, especially in the near wake. Owing to the coarse resolution in the far wake, larger deviations were observed here. As expected, the importance of the subgrid scale model significantly increased for the high-Re case in comparison with a low-Re case predicted earlier. A critical issue for LES is grid refinement which did not automatically lead to an improved agreement between the predicted results and the experimental measurements. Possible explanations are offered in the paper.