About scaling properties of relative velocity between heavy particles in turbulence

We present results obtained from high-resolution direct numerical simulations (DNS) of incompressible, statistically homogeneous and isotropic turbulence, up to a Taylor scale based Reynolds number Re-lambda similar or equal to 200 and with millions of heavy particles with different inertia. In our set-up, particles are assumed to be spherical and rigid, they simply move by viscous forces, such as the Stokes drag. The velocity statistics is found to be extremely intermittent, with an almost bi-fractal behavior. Here, we consider also a new data analysis for the stationary distribution of resealed longitudinal velocity difference and further assess the intermittent character of the heavy particles velocities, characterized by the presence of quasi-algebraic tails.