The monte carlo modelling of aerosol penetration through vertical parallel-plate channel in the case of point source of particles

摘要

Penetration of aerosols through a parallel-plate channel was solved as applied to the uniform,point,and segment sources of particles placed at the channel entry (Samsonov,2003).In the cases of a gaseous stream with a uniform-velocity profile (the slug flow),exact solutions to the diffusion equations were obtained for both the steady-state and pulse point emissions of particles.As regards the parabolic-velocity profile (the Poiseuille flow),it was proved that the common muster diffusion equations (Tan and Thomas,1972;or elsewhere) fail to depict local particle concentrations under pulse point emission of particles (so as for a pulse segment emission).This is due to the fact that after pulse emission of a bunch of particles into a channel with the Poiseuille flow,the distribution of aerosols should be non-stationary in time and non-uniform along the channel.Thus,the aforementioned equations,being stationary and uniform,do not hold for this case.As for the steady-state point emission into the Poiseuille flow,the above equations seem to be valid within the channel except for a small zone adjoining to the point emitter.Neglecting this non-stationary and non-uniform zone,the analytical solution was derived in the above-cited paper.