Brownian coagulation of fractal agglomerates: Analytical solution using the log-normal size distribution assumption

An analytical solution to Brownian coagulation of fractal agglomerates in t he continuum regime that provides time evolution of the particle size distr ibution is presented. The theoretical analysis is based on representation o f the size distribution of coagulating agglomerates with a time-dependent l og-normal size distribution function and employs the method of moments toge ther with suitable simplifications. The results are found in the form that extends the spherical particle solution previously obtained by K. W. Lee (J . Colloid Interface Sci. 92, 315-325 (1983)). The results show that the mas s fractal dimension has a significant effect on the size distribution evolu tion during coagulation. When the obtained solution was compared with numer ical results, good agreement was found. The self-preserving size distributi on of nonspherical agglomerates is discussed. (C) 2000 Academic Press.