基于结构演化的可压缩湍流的约束大涡模拟研究

发展高精度 WENO-紧致混合数值格式，对高 Mach数可压缩湍流以及Richtmyer-Meshkov不稳定演化为湍流的过程开展的数值模拟，获得高精度的湍流流场。引入正交分解和多尺度分析的方法，分析可压缩湍流能量在不同尺度上的传递和在剪切胀压过程上分配的机理，考察漩涡结构和激波结构的相互作用，获得可压缩湍流剪切和胀压的耦合的统计规律。对滤波后的流场进行分析，获得亚网格应力和热流对能量在剪切过程和胀压过程上分配的影响机制，建立相应的约束条件。将约束条件引入亚网格应力和热流的建模中；分析不同滤波方式对大涡模拟的影响；在高超声速边界层的约束大涡模拟中引入间歇因子的转捩模型。开展对高 Mach数可压缩湍流、可压缩湍流中惯性粒子的输运、高超声速边界层和RM不稳定性及其发展为湍流过程的约束大涡模拟，与直接数值对比，校验和改进大涡模拟方法。

The applicant and his team will develope a high-accurate WENO-Compact hybrid scheme for the high Mach number compressible turbulent flow. With this scheme, the direct numerical simulation of high Mach compressible turbulent flow and the evolution to the turbulence from Richtmyer-Meshkov instability will be performed. By introducing the multi-process decomposition and multi-scale anlysis, the energy transfer at different scale and distribution at shear process and dilation process are analyzed. From the interaction of shock and vortex, the mechanism of the coupling of shear process and dilation process will be obtained. By analyzing the filtered turbulence field, the effect of subgird scale stress and heat flux on the distribution of energy at shear and dilation process will be revealed. Then the physical constraints on the energy distribtion are derived and the noval constrained subgrid scale stress and heat flux models will be established. The large eddy simulation with different types of fliter will be tested. The constrained subgrid scale model with transition factor will be applied to the large eddy simulation of hypersonic turbulent boundary. With the novel constrained subgriad scale models, the large eddy simulation of high Mach number compressible turbulence, the transportation of inertial particles, RM intablity and hypersonic turbulent boundary will be performed and compared with the DNS results.