RELATIVE SPATIAL DIFFUSION IN TURBULENT MEDIA

Starting from the Langevin equation a nonlinear evolution equation des cribing the mean square distance of initially close tagged particles i n a turbulent medium is obtained. The equation is the same as that der ived for a turbulent plasma by Misguich and Balescu using renormalized kinetic theory. The approach is extended to incorporate stable drift in connection with the diffusion of macro particles in a turbulent flu id. The initial similar to t(3) and intermediate exponential growth of the mean square distance subsist even under the presence of stable dr ift in agreement with many confirmed observations.