Numerical Simulation of Particulate Motion in Turbulent Gas-Solid Channel Flow

A three-dimensional numerical model for turbulent shear flow in a channel with large Reynolds number is employed for the investigation of turbulent diffusion of finite inertia particulates. A stochastic nonlinear equation describing the motion of particles is integrated to obtain Lagrangian information. Special attention is paid to the effects of shear flow and wall boundary conditions. The results of these studies are compared to previous theoretical and empirical results. A cubic time dependency for separation is found at intermediate values of time while linear dependency is observed at large times. Schmidt numbers are always found to be smaller than one in the non-homogeneous region. It was concluded that special attention must be paid to appropriate computation times necessary to obtain a statistical equilibrium.