The authors introduce radial bias into off-lattice diffusion-limited aggregation in order to simulate radial anisotropy present in experiments on viscous fingering in liquid crystals. For large cluster sizes the model is also expected to provide information about the asymptotic shape of the ordinary off-lattice diffusion-limited aggregates. They find that for large enough radial bias the overall shape of the clusters becomes star-like with a spontaneously selected number of main arms which is either four, or less frequently five. The crossover to this structure is accompanied by a change in the radius of gyration exponent which approaches the value 1.5 previously observed for systems with axial anisotropy or very large clusters grown on the square lattice.
ASJC Scopus subject areas
- Statistical and Nonlinear Physics
- Mathematical Physics
- Physics and Astronomy(all)