Dispersion of discrete particles by continuous turbulent motions. Extensive discussion of the Tchen’s theory, using a two-parameter family of Lagrangian correlation functions

Abstract

The theory of dispersion of discrete particles by continuous turbulent motions is first expressed in a 3-D formalism, as a synthesis between the 1-D Tchen’s theory of dispersion and the 3-D Batchelor’s theory of diffusion. Then it is exemplified with the aid of a two-parameter Frenkiel family of Lagrangian correlation functions, taking into account the Basset’s term or neglecting it. It is then shown and explained that even dense discrete particles may disperse faster than fluid particles. That work is included in a more general framework aiming at modeling and predicting the behavior of discrete particles in turbulent flows.