Brownian diffusion of aerosol particles in slit-like channel with moving gas for uniform, point, and segment sources positioned at channel inlet

Abstract

Analytical solutions to the equations of Brownian diffusion were derived to depict the outlet dis tributions of local concentrations of particles penetrating through a slit like channel for both the spatially uniform and non uniform sources of particles at the channel inlet. The "point" and "segment" sources posi tioned at the inlet form the non uniform entering concentrations. The sources could emit particles in either the single pulse or pulse periodic (steady state) operating mode. The solutions were obtained for both the laminar gas stream with parabolic velocity profile (the Poiseuille flow) and the stream with plane profile (the slug flow). The physical and mathematical features of the Brownian diffusion were considered with respect to the pulse and the pulse periodic (steady state) point and segment emissions of particles in the Poiseuille flow. The Monte Carlo simulation of the Brownian motion of particles was performed to compare the analytical and the simulated distributions of particles for the point source.