Large eddy simulation of a 3-D spatially developing turbulent round jet  

作　　者：ZHANG HuiQiang RONG Yi WANG Bing WANG XiLin 

机构地区：[1]School of Aerospace, Tsinghua University, Beijing 100084, China

出　　处：《Science China(Technological Sciences)》2011年第11期2916-2923,共8页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 50176027 and 50706021);a grant from the Research Committee of The Hong Kong Polytechnic University (Grant No.G-U294)

摘　　要：A three-dimensional large eddy simulation （LES） of a spatially developing round jet is carried out in cylindrical coordinates using a dynamic subgrid model with strong inflow instability. Evolutions of large-scale vortex structures represented by tangential vortices are obtained and compared with flow visualization. Also presented are three-dimensional spatial evolutions of coherent structure, which are of quasi two-dimensional Kelvin-Helmholtz instability and vortex rings as well as breaking up of the vortex rings with fully three-dimensional characteristics. Predicted results of mean velocity and turbulent intensity agree well with experiments. They are also compared with the results predicted by LES using standard Smagorinsky model and show good self-similarity. Turbulence spectrum of the predicted velocity shows the -5/3 decay for higher wave number, as expected for turbulent round jet flows. In addition, fl-test and y-test are carded out for the instantaneous velocity, showing that the present LES method can successfully predict the hierarchical structure of round jet.

关 键 词：large eddy simulation round jet spatially developing flow large-scale structure hierarchical structure 

分 类 号：O359[理学—流体力学] O357.5[理学—力学]