二维超声速混合层的大涡模拟

The Large Eddy Simulation of Two-Dimensional Supersonic Mixing Layer

对二维超声速混合层流动进行大涡模拟。采用五阶精度的WENO格式求解大尺度涡的控制方程,小尺度涡的作用采用Smagorinsky亚格子模型进行模拟。模拟结果再现了二维超声速混合层拟序结构,计算得到了涡组对、合并等现象。通过对流场不同位置压力振荡历程的频谱分析,对超声速混合层中的谐波变化规律作了初步探讨。计算得到的速度剖面的时均统计结果与实验结果相比,吻合程度较好。

Large eddy simulations are conducted to investigate the coherent structures of a two-dimensional supersonic mixing layer. The Governing equations of large scale eddies are solved with fifth-order WENO scheme and the effect of small scale eddies is simulated with Smagorinsky subgrid scale model. The results show that the development procedure of large structures and reveal the behavior of large eddies. Frequency spectrum analysis of the unsteady pressure data is performed to investigate the acoustic characteristics of different streamwise location in the mixing layer. Time-averaged velocity profdes obtained from the simulation are consistent with the experimental data.