LARGE-EDDY SIMULATION OF THREE-DIMENSIONAL VORTICAL STRUCTURES FOR AN IMPINGING TRANSVERSE JET IN THE NEAR REGION  

作　　者：FAN Jing-yu ZHANG Yan WANG Dao-zeng 

机构地区：[1]Shanghai Institute of Applied Mathematics and Mechanics, Shanghai University, Shanghai 200072, China, [2]Key Laboratory of Advanced Display and System Applications （Shanghai University）, Ministry of Education and SMIT Center, Shanghai University, Shanghai 200072, China [3]Department of Applied Mechanics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden [4]Shanghai Institute of Applied Mathematics and Mechanics, Shanghai University, Shanghai 200072, China

出　　处：《Journal of Hydrodynamics》2007年第3期314-321,共8页水动力学研究与进展B辑（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant No. 10572084);Shanghai Leading Academic Discipline Project (Grant No. Y0103)

摘　　要：The three-dimensional vortical structures for an impinging transverse jet in the near region were numerically investigated by means of Large-Eddy Simulation （LES）. The LES results reproduced the skewed jet shear layer vortices close to the jet nozzle and the scarf vortex in the near-wall zone in good agreement with the experimental observations. Different vortical modes in the skewed jet shear layer close to the jet nozzle were identified depending upon the velocity ratio between jet and crossflow, namely changing from an approximately axisymmetric mode to a helical one with the velocity ratios varying from 20 to 8. Moreover, the scarf vortex wrapped around the impinging jet in the near-wall zone showed distinct asymmetry with regard to its bilateral spiral legs within the near region. And the entrainment of the ambient crossflow fluids by the scarf vortex in the near-wall zone was appreciably influenced by its asymmetry and in a large part occurred on the surface of the spiral roller structures in the course of spreading downstream.The three-dimensional vortical structures for an impinging transverse jet in the near region were numerically investigated by means of Large-Eddy Simulation （LES）. The LES results reproduced the skewed jet shear layer vortices close to the jet nozzle and the scarf vortex in the near-wall zone in good agreement with the experimental observations. Different vortical modes in the skewed jet shear layer close to the jet nozzle were identified depending upon the velocity ratio between jet and crossflow, namely changing from an approximately axisymmetric mode to a helical one with the velocity ratios varying from 20 to 8. Moreover, the scarf vortex wrapped around the impinging jet in the near-wall zone showed distinct asymmetry with regard to its bilateral spiral legs within the near region. And the entrainment of the ambient crossflow fluids by the scarf vortex in the near-wall zone was appreciably influenced by its asymmetry and in a large part occurred on the surface of the spiral roller structures in the course of spreading downstream.

关 键 词：Large-Eddy Simulation （LES） impinging jet CROSSFLOW vortical structure ENTRAINMENT 

分 类 号：O358[理学—流体力学]