Comparative assessment and analysis of Rortex vortex in swirling jets  

作　　者：Nan Gui Liang Ge Peng-xin Cheng Xing-tuan Yang Ji-yuan Tu Sheng-yao Jiang 

机构地区：[1]Institute of Nuclear and New Energy Technology, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Tsinghua University, Beijing 100084, China [2]School of Engineering, RMIT University, Melbourne, VIC 3083, Australia

出　　处：《Journal of Hydrodynamics》2019年第3期495-503,共9页水动力学研究与进展B辑（英文版）

基　　金：National Natural Science Foundations of China(Grant No.51576211);the Science Fund for Creative Research Groups of National Natural Science Foundation of China(Grant No.51621062);the National High Technology Research and Development Program of China(863 Program,Grant No.2014AA052701);the Foundation for the Author of National Excellent Doctoral Dissertation of China(FANEDD,Grant No.201438).

摘　　要：Recently, a new definition, called Rortex, was proposed to quantify the purely rotational motion of fluids. In this work, based on the DNS data, the Rortex is used to assess and visualize the rotational motion and structure of the vortex in swirling jets in comparison with other kinds of vortex criteria, including Q , λ2,vorticity and Ω criteria. The Rortex vector,Ω, Q and criteria are found to be better than the vorticity criterion for the vortex core identification. The vector triangle formed by the Rortex R , the nonrotational shear S , and the vorticity R is analyzed to give mechanical explanations, especially of the effect of the non-rotational shear on the rotation of fluids. In addition, the probability density distributions (PDF) of the Rortex R , the nonrotational shear S, and the vorticity R are computed. The peak value of the PDF of the vorticity could be used to explain the pure rigid rotation effect and the combination effects of the rigid rotation and the non?rotational shear.

关 键 词：Swirling flow VORTEX Rortex direct NUMERICAL simulation RIGID ROTATION non-rotational SHEAR 

分 类 号：O3[理学—力学]