DIRECT NUMERICAL SIMULATIONS OF TURBULENT CHANNEL FLOWS WITH CONSIDERATION OF THE BUOYANCY EFFECT OF THE BUBBLE PHASE  

作　　者：LIU Nan-sheng CHENG Bao-guo QUE Xia LU Xi-yun 

机构地区：[1]Department of Modem Mechanics, University of Science and Technology of China, Hefei 230026, China [2]Department of Computer Science and Technology, Hefei University of Technology, Hefei 230009, China

出　　处：《Journal of Hydrodynamics》2011年第3期282-288,共7页水动力学研究与进展B辑（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.10772173,10972211 and 11072236);the Fundamental Research Funds for the Central Universities;the Science and Technology Innovation Foundation of the Chinese Academy of Sciences(Grant No.CXJJ-11-M69)

摘　　要：Turbulent channel flows with consideration of the buoyancy effect of the bubble phase is investigated by means of the Direct Numerical Simulation （DNS）. This two-phase system is solved by a two-way coupling Lagrangian-Eulerian approach. The Reynolds number based on the friction velocity and the half-width of the channel is 194, and the gravitational acceleration varies from -0.5 to 0.5, ranging from the upflow to the downflow cases. This study aims to reveal the influence of buoyancy on the turbulence behavior and the bubble motion. Some typical statistical quantities, including the averaged velocities and velocity fluctuations for the fluid and bubble phases, as well as the flow structures of the turbulence fluctuations, are analyzed.Turbulent channel flows with consideration of the buoyancy effect of the bubble phase is investigated by means of the Direct Numerical Simulation （DNS）. This two-phase system is solved by a two-way coupling Lagrangian-Eulerian approach. The Reynolds number based on the friction velocity and the half-width of the channel is 194, and the gravitational acceleration varies from -0.5 to 0.5, ranging from the upflow to the downflow cases. This study aims to reveal the influence of buoyancy on the turbulence behavior and the bubble motion. Some typical statistical quantities, including the averaged velocities and velocity fluctuations for the fluid and bubble phases, as well as the flow structures of the turbulence fluctuations, are analyzed.

关 键 词：Direct Numerical Simulations （DNS） turbulent bubbly flow upflow/downflow turbulence fluctuations bubble statistics turbulence structures 

分 类 号：O357.5[理学—流体力学] TU46[理学—力学]