绕串列方柱流动的三维大涡仿真

Large Eddy Simulation of Three-Dimensional Flow Past Two Square Cylinders in Tandem

在风场强度分析方法的研究中,为了深入研究串列方柱绕流中流动情况,详细分析方柱受力情况,采用LES模型,对绕串列方柱的三维湍流流动进行了数值仿真,着重研究了流场形态、升阻力系数变化曲线,给出了流场中两方柱在较高雷诺数下受到的升力和阻力的变化情况。结果表明串列方柱绕流的流动特征在很大程度上取决于间距的大小,且间距存在一临界值,间距比从小于临界值变化到大于临界值将带来流体动力学参变量的突然变化,并且临界间距随着雷诺数的增加而减小。

In order to investigate the characteristics of the flow past square cylinders deeply, and understand the dynamic forces acted on the square cylinders in detail, the paper employed a large eddy simulation （LES） to simulate three - dimensional turbulent flow past two square cylinders in tandem. The investigation focused on finding of flow patterns, time histories of lift and drag coefficients. Variation of fluctuating drag and lift on two prisms was given at higher Reynolds numbers. The results indicate that the qualitative nature of flow around two cylinders in a tandem depends on the distance between the prisms. Moreover, a critical value exists in the distance between the prisms. Sudden changing happened in flow dynamics when the distance changed from below the critical value to above the critical value. The critical distance was also reduced with the increasing of Reynolds numbers.