Diffusion limited aggregation with directed and anisotropic diffusion

Abstract
Fractal aggregates obtained from diffusion limited growth processes are studied. Numerical simulations are reported for a two-dimensional cluster growing on a basal line. For isotropic diffusion this model behaves as the spherically growing model of Witten and Sander. It is found that directed diffusion renders the cluster compact while anisotropic diffusion apparently yields a continuously varying fractal dimension