Hybrid simulation method for agglomerate evolution in driven granular gases

Aims. We present a new hybrid simulation method for protoplanetary dust evolution that is efficient and takes into account the complex fragmentation and agglomeration dynamics. We applied it to simulate the evolution of agglomerate size distributions for turbulent, charged systems. Methods. The hybrid method combines kinetic Monte Carlo and discrete element simulations in such a way that the expensive latter is only deployed when two agglomerates collide. This method can easily be extended to include additional driving mechanisms, interactions, and the effects of inhomogeneities. Results. Our simulations reveal an emerging steady state in the size distribution. Due to the efficiency of our method, we are able to extend previous results with improved statistics for the size distribution of large agglomerates; in addition to the previously reported power law, we find a regime with an exponential decay.