Re=3 900的圆柱绕流湍流模拟对比研究

Abstract

The flow past a cylinder at a Reynolds number of 3 900 is addressed with the delayed DES (DDES) and constrained large-eddy simulation (CLES). The experiments and numerical simulations in this case have been extensively analyzed in previous researches. It is commonly recognized that the flow structures and recirculation length are closely related to the dispersion and dissipation properties of the scheme. Under such consideration, an optimized scheme is chosen and validated for several typical flows with multi-scale structures and strong shocks. Then, the DDES and CLES are performed to obtain pressure distribution, mean velocity profiles and the turbulence statistics in the near wake. By comparing the results from calculations with the experimental data, it is found that the averaged quantities from the CLES agree slightly better with the experimental data than those from the DDES. In the instantaneous flow field, complicated structures are captured by both the DDES and the CLES. A significant difference between them is that small-scale motions can be observed in the near-wall region for the CLES. Lastly, though the CLES predicts the mean statistics slightly better, the implementation of the CLES is much more complex than that of the DDES.