Large scale fractal aggregates using the tunable dimension cluster–cluster aggregation Original Research Article

The tunable dimension cluster–cluster aggregation (tdCCA) [R. Thouy, R. Jullien, J. Phys. A: Math. Gen. 27 (1994) 2953] provides a computational model for creating fractal aggregates with a tunable fractal dimension. A straightforward implementation of this model requires a computational effort scaling with O(Ntotal4) of the number of particles Ntotal. By applying two minor changes to the algorithm the computational effort can be reduced to O(Ntotal2) and allows an efficient parallel implementation of the tdCCA. On a modern parallel computer a fractal aggregate of one million particles has been built in less than 24 h.