嵌入式RANS/LES混合方法在槽道流动数值模拟中的应用  

Applying Embedded Hybrid RANS / LES Method to Channel Flow

作　　者：李栋[1] 王翔宇[1] 

机构地区：[1]西北工业大学翼型叶栅空气动力学国防科技重点实验室,陕西西安710072

出　　处：《西北工业大学学报》2015年第5期799-803,共5页Journal of Northwestern Polytechnical University

基　　金：国家自然科学基金面上项目(11072200)资助

摘　　要：与传统整体式RANS/LES混合方法相比,嵌入式RANS/LES混合方法不再依靠改进后的湍流模型本身或网格疏密自动划分流场中的RANS区域和LES区域,而是通过对流动现象的预估,人为将LES区域嵌入到RANS区域,从而使RANS区过渡到LES区的交界面尽可能与流向垂直,方便合理附加额外的湍流脉动信息。这样做不但确保了LES在某些复杂流动区域彻底支配地位,更重要的是能够避免RANS区对LES区解析湍流发展的污染和抑制。将槽道流场划分为上游RANS区和下游LES区,在经典的SST-DES模型基础上,采用合成涡方法生成交界面的湍流信息,取得了良好的模拟结果。As compared with traditional global hybrid RANS/LES method, embedded hybrid RANS/LES method does not treat the whole field as different RANS or LES regions automatically based on the turbulence model itself or whether the mesh is fine or not. It is aimed to embed any LES part to the background RANS flow artificially so that the interface between RANS and LES is set vertically to the streamwise direction and the extra resolved turbulence information in the interface can be easily and rationally added. That means, it can not only make sure that LES con- trois the flow principles totally in the regions of complex flow phenomena but also avoid the pollution from RANS and overcome the delay of resolved turbulence in LES regions. In this paper channel flow is divided into upstream RANS and downstream LES regions, and SST-DES is used as the basic hybrid model, together with the additional turbulent fluctuations generated from synthetic eddy method in the interface, which finally lead to a satisfactory sim- ulation.

关 键 词：嵌入式RANS/LES混合方法 SST-DES 合成涡方法 槽道流动 数值模拟 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]