LOGNORMAL SIZE DISTRIBUTIONS IN PARTICLE GROWTH-PROCESSES WITHOUT COAGULATION

A new model is proposed to explain lognormal particle size distributio ns found in vapor growth processes such as gas evaporation, without in voking coagulation. In the model, particles are moving by diffusion an d drift through a finite growth region. The particle size is assumed t o be a power function of growth time, and the final size distribution is determined by the first passage times. By computer simulation, logn ormal size distributions and scaling laws interrelating the distributi on parameters, the size of the growth region, and the drift speed were found.