A stochastic description of wall sources in a turbulent field. Part 3: Effect of gravitational settling on the concentration profiles

A stochastic method, which uses a modified Langevin equation to represent the fluid turbulence seen by the particles, is used to determine the fully-developed concentration profiles that exist for the turbulent flow of a dilute suspension of spheres in a horizontal channel. Particles with a wide range of inertial time constants and settling velocities are studied. The validity of using the Boussinesq approximation to represent turbulent mixing is explored.