A MODIFIED BALLISTIC AGGREGATION MODEL

The standard ballistic aggregation model assumes that the particles th at are added to a growing agglomerate follow straight-line trajectorie s. The finite viscosity of real fluids, however, biases the flow of li quid around, rather than through, the agglomerate. The result is that the particles, which follow streamlines in the fluid, will tend to be deposited near the periphery of the growing agglomerate. A modificatio n is made to the ballistic aggregation model to account for this effec t, and the geometry of the resultant structures is characterized, The simulation results suggest that even under conditions where convection dominates particle motion, branched open structures are likely to be formed. (C) 1995 Academic Press, Inc.