An overview about the study of downwash effects on dispersion of airborne pollutants

The aim of the present work is to give an overview about the state of the art of the study of the downwash phenomena of airborne pollutants. Accounting for the downwash of pollutant dispersion is of interest because it can contribute to the prevention of dangerous situations by determining in advance what configuration of buildings, stacks, and effluents could cause a high concentration of harmful effluents in a particular area. Recent and less recent studies concerning both building and stack downwash are presented. Some of the presented models are well established and implemented in regulatory air pollutions codes, while other ones are more sophisticated and still under development.