抄録
The behavior of aerosol particles of sub-micron diameter undergoing Brownian coagulation, Brownian diffusion and gravitational settling was studied by numerically solving the equation of population balance and by experimentally observing the change of aerosol properties with time. In calculation, two dimensionless parameters, which are determined by the initial properties of aerosols and vessel dimension in which aerosols are suspended, were introduced to evaluate the magnitude of influence of Brownian coagulation and Brownian diffusion on gravitational settling. The results of numerical calculation were indicated by graphical representation, which is usable for quantitative estimation of the magnitude of these two effects. These computational results were found to be in good agreement with the experimental results obtained by an ultramicroscopic technique of particle size analysis.