LES of chemically reactive pollutant transport in urban areas

Urban areas refer to the areas with high buildings and streets. Ordinarily the scale of urban areas is about one or two kilometers. The pollutant transporting in this area will be impacted by both buildings and air flow of high altitude.

In order to accurately simulate the large scale turbulent flow in urban areas, the ordinary RANS method give way to LES method. Because the size of urban areas are very large, the number of the grids grows rapidly. What we have to do is to find a method solving this problem quickly and accurately.

The air pollutant near the ground usually exists in gaseous form, such as nitrogen oxides, sulfur oxides and carbon oxides. Chemically reactive pollutant is the kind of pollutant who can easily take part in the reaction in air, such as carbon monoxide (CO), sulfur dioxide (SO2) and Nitric oxide (NO).