DEPOSITION OF AEROSOLS ON SURFACES IN A TURBULENT CHANNEL FLOW

A digital simulation procedure for studying deposition of aerosol particles in a turbulent channel flow is developed. An empirical mean velocity profile and the experimental data for turbulent intensities are used in the analysis. The instantaneous fluctuating velocities are simulated as continuous Gaussian random fields. Effects of Brownian diffusion, Saffman lift force, gravity and particle-surface interactions are included in the computational model. Starting with an initially uniform concentration near the wall, ensembles of particle trajectories are generated and statistically analyzed. Several simulations for deposition of aerosol particles of various sizes are performed and the corresponding deposition velocities are evaluated. The results are compared with the existing experimental data and those obtained by empirical equations. The effect of particle rebound from surface on particle deposition rate is also studied.