Effects of wall roughness in a gas-particle turbulent vertical channel flow

Authors: Fukagata, K., Zahrai, S., Bark, F.H., Kondo, S.
Document Type: Conference
Pubstate: Published
Journal: Turbulence and Shear Flow Phenomena - 2
Volume: II   117-122
Year: 2001


Gas-particle turbulent channel flows are studied using the Lagrangian particle tracking coupled with large eddy simulation (LPT-LES). A turbulent channel flow of air at Re_=644, loaded with 70 ƒÊm copper particles at a mass fraction of 2 % and a flow with 50 ƒÊm glass particles at the same condition are simulated. Small amount of roughness is introduced at the walls and its influence on the statistics of particles is investigated. The statistics of the highly inertial particles, i.e. 70 \mu m copper particles, are found to be largely modified in the whole channel due to the presence of the wall roughness, and a tendency similar to the experimental data by Kulick et al. (1994) is observed. The statistics of the particles with smaller inertia, i.e. 50 ƒÊm glass particles, are less influenced by the wall roughness assumed in the present study.