Theoretical study of atmospheric diffusion of radioactive and industrial pollutants

The present thesis deals with the study of atmospheric dispersion models and some of their applications. In chapter I, we presented a survey study of the atmospheric dispersion models and their mechanisms. The Gaussian plume model, Eulerian dispersion model and Lagrangian dispersion model are discussed. The concepts of plume rise, wind velocity profiles also are investigated.in chapter l l, an analytical solution of the atmospheric diffusion equation for different stability conditions is performed. the numerical simulation to gaussian plume equation is performed via Triad model to get the predicted concentration and compared with the observed one. we adopted two approaches to the derived calculations, more over the concentrations (predicted and observed) are measured here the full wind field is considered, ( TRIADYES ) or the wind field measured near the source (TRIADNO). the statistical analysis of the output runs is estimated and the difference between the two approaches is outlined