Turbulent dispersion in a non-homogeneous field

Dispersion of fluid particles in non-homogeneous turbulence was studied for fully developed flow in a channel. A point source at a distance of 40 wall units from the wall is considered. Data obtained by carrying out experimen ts In a direct numerical simulation (DNS) are used to test a stochastic mod el which utilized a modified Langevin equation. All of the parameters, with the exception of the time scales, are obtained from Eulerian statistics. G ood agreement is obtained by making simple assumptions about the spatial va riation of the time scales.