A Particulate Diffusion Experiment

Abstract

Results are presented from a series of field experiments at Suffield Experimental Station. In these experiments, glass spheres were released from a continuous elevated point source above gently tolling prairie terrain. The standard deviations of the distributions of particulate ground deposit across each sampling arc were well forecast, in stationary conditions, by Hay and Pasquill's technique of equating particulate standard deviation with the standard deviations of appropriately sampled and averaged vane angle data. The prediction of the crosswind-integrated deposit and its variation with distance from the emission point appeared to be more difficult because the ?scale? of these field experiments rendered the prediction equations sensitive to the choice of atmospheric diffusion parameters. The predictions of crosswind-integrated deposits were improved If the most appropriate values of the Lagrangian-Eulerian turbulence scale factor were used.