Affiliations: Department of Mechanics, State Key Laboratory of Fluid
Power Transmission and Control, Zhejiang University, Hangzhou 310027,
China | Institute of Marine and Coastal Sciences, Rutgers
University, New Brunswick, New Jersey, USA
Abstract: Lattice Boltzmann method and elastic particle collision model were
used to investigate the sedimentation of short cylindrical pollutant particles
with mechanical contacts for varying bulk number density ε and terminal
Reynolds number Re_T. The corresponding experiments were
performed as a comparison. The clusters of pollutant particles with an inverted
"T" structure were observed, the pollutant particles for high ε and large
Re_T scattered wider than that for low ε and small
Re_T. The sedimentation velocities increased suddenly at the
initial stage, then decreased drastically, after that swayed around and
approached to a steady value. The time to steady state did not depend on
ε and Re_T. The effect of particle interactions was to
hinder the average sedimentation velocity, and hindrance was directly
proportional to ε. The orientation distributions of pollutant particles
depended on Re_T and ε, especially on the former. Both
the standard deviations of vertical and horizontal velocity, the former was
larger than the latter, were nearly independent on ε and
Re_T.
