Numerical simulation of flow patterns in dense pneumatic conveying at different superficial gas velocities

Due to the problem in available numerical simulations of flow patterns in dense pneumatic conveying,a new mathematical model,which uses solid-phase volume concentration of local space and kinematic characteristics of clusters to describe the interactions between particles,was proposed in this paper.This model was first used to numerically simulate the dense pneumatic conveying(even for the packing of particles),and then used to numerically study the flow behavior of dense phase pneumatic conveying in horizontal pipe at high pressures,in which the separation and sedimentation between gas phase and solid phase in the conveying process were investigated.The simulation results also illustrated the evolving characteristics of flow patterns such as dune flow and plug flow,which are consistent with the experimental phenomena.Moreover,some rules of flow patterns were revealed by qualitatively analyzing the distribution of solid-phase flow patterns at different superficial gas velocities.The results show that the new model is appropriate and can be used to study the dense pneumatic conveying.