Analysis of non-spherical polydisperse particle growth in a two-dimensional tubular reactor

Polydisperse aggregate particle growth considering coalescence, coagulation, generation and spatial transport processes is studied in a two-dimensional reactor for the first time. Effects of two-dimensional spatial transport processes, such as convection, diffusion, deposition and thermophoresis as well as nucleation, coagulation and coalescence are of primary interests. An efficient particle dynamics model based on two sets of coupled sectional equations (J. Aerosol Sci. 32 (2001) 565) is used to facilitate the severe computation loads for analyzing the growth of non-spherical polydisperse particles in an axi-symmetric two-dimensional geometry. Fluid dynamics calculations indicate the existence of non-uniform distributions of temperature and flow fields in the radial direction as well as in the axial direction inside the reactor. Particle dynamics simulations also demonstrate the significant inhomogeneous spatial distributions of the characteristics of aggregate particles. The present two dimensional calculations for reactor temperatures and particle size distributions are in agreement with the previous experimental data. The validity of simplified one-dimensional analysis is also evaluated against the present two-dimensional analysis. While the one-dimensional analysis agreed well with the spatially two-dimensional one for the cases of low flow rates, it resulted in significant errors for high flow rates. (C) 2003 Elsevier Science Ltd. All rights reserved.