Particle agglomeration and dispersion in fully-coupled turbulent channel flow using large eddy simulation and discrete element method

摘要

The work described in this paper employs large eddy simulation and the discrete element method to study particle-laden flows, including particle dispersion and agglomeration, in a horizontal channel. The particle-particle interaction model used is based on the Hertz-Mindlin approach with Johnson-Kendall-Roberts cohesion to allow the simulation of Van der Waals forces in the dry air flow considered. The influence of different particle surface energies, particle size, particle concentration and flow Reynolds numbers on particle agglomeration is investigated. The turbulent structure of the flow is found to dominate the motion of the particles, although the agglomeration rate is found to be strongly influenced by all of the variables noted above, with most of the particle-particle interactions taking place at locations close to the channel walls, aided by the higher turbulence levels and concentration of particles in these regions.