Modeling of dynamic deposition and filtration processes of airborne particles by a single fiber with a coupled lattice Boltzmann and discrete element method

Abstract

Airborne particulate matter (PM) pollution has caused many deleterious effects on atmospheric environment and people’s health. Fiber filtration has been regarded as one of the efficient and economical ways for removing particles from gas streams. To reveal the dynamic capture processes of airborne particles by fibrous filters, and their effects on filtration performance, a lattice Boltzmann modeling approach coupled with discrete element method (LB-DEM), is used for simulations of airborne particle deposition on an individual fiber. The mutual influences between the dynamic particle transport/deposition and the fluid flow are considered. The model well predicts the formation of the dendrites and the dynamic progression of the deposit under different capture mechanisms. The adhesion parameter is proved to have a dominant effect on the dynamic deposition processes and filtration performance. Increases in adhesion parameter lead to looser particle dendrites, faster deposition rates and better filtration efficiencies. The smaller particles tend to have larger pressure drops and more compact dendrite structures at the same deposition mass.