Numerical investigation of the effect of sub-grid scale eddies on the dispersed particles by LES/FDF model  

作　　者：JIN HanHui1,CHEN SuTao1,CHEN LiHua1 & FAN JianRen2 1 School of Aeronautics and Astronautics,Zhejiang University,Hangzhou 310027,China 2 State Key Lab of Clean Energy Utilization,Zhejiang University,Hangzhou 310027,China 

出　　处：《Science China(Technological Sciences)》2010年第5期1304-1308,共5页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No.10502044,10772162);the Defense-based research project(Grant No.A1420080144);the Major projects on control and rectification of water body pollution (Grant No.2009ZX07424-001)

摘　　要：An LES/FDF model was developed by the authors to investigate the SGS effect on the particle motion in the gas-particle two-phase plane wake flow.The simulation results of dispersion rate for different particles were compared with the results without using the FDF model.It was shown that the large eddy structure is the dominant factor influencing the particle diffu-sion in space for small particles(small Stokes-number particles),but for intermediate or large diameter particles,the influence of the sub-grid scale eddies on the dispersion rate is in the same order as that of the large eddies.The sub-grid scale eddies increase the particle dispersion rate in most time,but sometimes they decrease the dispersion rate.The sub-grid scale particle dispersion rate is decided not only by the intensity of sub-grid scale eddies and the Stokes number of the particles,but also by the large eddy structure of the flow field.For the particles in isotropic turbulence,the dispersion rate decreases as the particle diameter increases.An LES/FDF model was developed by the authors to investigate the SGS effect on the particle motion in the gas-particle two-phase plane wake flow.The simulation results of dispersion rate for different particles were compared with the results without using the FDF model.It was shown that the large eddy structure is the dominant factor influencing the particle diffu-sion in space for small particles(small Stokes-number particles),but for intermediate or large diameter particles,the influence of the sub-grid scale eddies on the dispersion rate is in the same order as that of the large eddies.The sub-grid scale eddies increase the particle dispersion rate in most time,but sometimes they decrease the dispersion rate.The sub-grid scale particle dispersion rate is decided not only by the intensity of sub-grid scale eddies and the Stokes number of the particles,but also by the large eddy structure of the flow field.For the particles in isotropic turbulence,the dispersion rate decreases as the particle diameter increases.

关 键 词：MULTIPHASE flow large EDDY simulation filtered density function TURBULENCE sub-grid 

分 类 号：O357.5[理学—流体力学]