A chemical vapor synthesis (CVS) process for synthesizing nano-sized aluminum powder as a precursor for various hydrogen storage materials was simulated by the use of computational fluid dynamic modeling. The fluid flow, heat transfer and chemical reaction phenomena taking place inside the reactor were analyzed together with particle formation and growth in the CVS process. The temperature, velocity and particle size distribution fields inside the reactor were computed. Chemical reaction rate and population balance model were used to calculate the particle formation and growth. The particle size computed by the program was compared with the experimental data, and the calculated average size of the final product particles was consistent with those obtained in the experimental work. (C) 2009 Elsevier B. V. All rights reserved.