改进SST湍流模型在分离流中的应用

Application of the improved SST turbulence model for separated flow

针对标准SST模型无法对分离流动进行准确的数值模拟的问题,本文根据分离流动的特性,在传统SST模型的基础上增加了能量传递耗散项,提升了该模型对分离流动的模拟精度。以开源软件Open FOAM为平台,运用改进的SST湍流模型,对亚临界雷诺数情况下的圆柱绕流算例进行计算,并结合已有的实验结果,与原始SST模型的计算结果进行对比。结果证明:改进的SST模型能有效弥补原始SST模型在模拟分离流时,漩涡脱落强度偏小的缺陷,对于亚临界雷诺数下的分离流动的数值模拟具有良好效果。

Given that the standard SST model often fails to produce accurate numerical simulations for separated flow, the simulative precision of the separated flow model can be improved by accounting for the characteristics of separated flow and the increased energy-transfer dissipation item on the basis of the traditional SST model. A flow around a circular cylinder under subcritical Reynolds number was calculated by applying the improved SST turbulence model with the open-source software OpenFOAM as the platform. The calculation results of the original SST model were compared with that of the proposed model. Results showed that the improved SST model can effectively remedy the defect of small-vortex shedding strength in separated flow simulated by the original SST model. Moreover, it has an excellent effect on the numerical simulation of separated flow under subcritical Reynolds number.