Role of basset force on particle deposition in stagnation flow

Abstract

Deposition of nondiffusive aerosols in stagnation point flow was examined. The complete equations of particle motion, including the Basset and virtual mass effects for a particle in a linear velocity field with a constant body force acting on it, were solved, and a general solution was obtained from which particle trajectories and velocities may be predicted. It was found that Basset force generally tends to hinder deposition by keeping particles in flight for longer times than in their absence. However, when particle Stokes numbers are sub-critical Basset force can actually enhance particle fluxes. As a consequence, inertial enrichment of particle concentrations at the deposition plane was increased. An analytical solution for a particle coming to rest in a quiescent fluid was obtained and compared to numerical results of Pearcey and Hill [Pearcey, T. and Hill, G. W. (1956) Aust. J. Phys. 9, 19–30].