Lagrangian Similarity Modeling of Vertical Diffusion from a Ground-Level Source

摘要

Several alternate Lagrangian similarity predictions of turbulent diffusion in a thermally-stratified turbulent shear flow were compared with the Prairie Grass ground-level, crosswind-integrated tracer concentration data. The best agreement with the data was found by assuming that the eddy diffusivity K of a passive contaminant corresponds to that of heat, by using an exponent r equal to 1.5 or 2 in the vertical contaminant distribution exp(-(anti z/b anti z)/sup r/), and by using Chaudhry and Meroney's equation-d anti z/dx = K(anti z)/anti zu (c anti z) for the downwind growth of the mean height anti z of the diffusing contaminant. (ERA citation 05:014156)