518 固気混相チャネル乱流における粒子の数密度分布(混相流・自由表面を含む流れの諸問題II)(OS.7 混相流・自由表面を含む流れの諸問題)

概要

論文の詳細を見る
In order to study the preferential concentration of particles in turbulent flows, Lager Eddy Simulation (LES) of downward fully particle-laden channel turbulent flows wwr performed with considering inter-particle collisions and fluid Sub-Grid Scale (SGS) components for Reynolds number 180 and 644 respectively. Trajectories individual of 5 different particles were pursued with Eulerian-Largrangian approach, where the SGS components were parametrized using Dynamic Random Walk SGS (DRW) model proposed by LEI (2000), and the inter-particle collisions were dealt with the deterministic DNS method. The effects of Stokes numbers, turbulence SGS components and inter-particle collisions on the structure of particle distributions were discussed. It was verified that the maximum departure from randomness a when the ratio of the particle's aerodynamic response time to the Kolmogorov time scale of flow was approximately one. Furthermore, the degree of preferential concentration are selectively associated with the SGS components of turbulence, the simulation rsults showed that the particles when its response time one order are smaller than Kolmogorov time scale of flow aren't nearly in conflict even though the particle number density is high.
一般社団法人日本機械学会の論文
2001-03-09