Particle dispersion in synthetic turbulent flows

We study particle dispersion advected by a synthetic turbulent flow from a Lagrangian perspective and focus on the two-particle and cluster dispersion by the flow. It has been recently reported that Richardson's law for the t wo-particle dispersion can stem from different dispersion mechanisms, and c an be dominated by either diffusive or ballistic events. The nature of the Richardson dispersion depends on the parameters of our flow and is discusse d in terms of the values of a persistence parameter expressing the relative importance of the two above-mentioned mechanisms. We support this analysis by studying the distribution of interparticle distances, the relative velo city correlation functions, as well as the relative trajectories.