Impact of buildings’ configuration in an urban context on the spread pattern of NO₂ and indoor air quality: A CFD simulation

The influence of the building’s configuration on the air flow pattern and the amount of pollutant entering the buildings was investigated. Six common forms of low-rise buildings in Shiraz City were evaluated as investigated patterns. Each of these forms were placed in four rotation modes (24 case studies in total) in an urban regular pavilion-shaped context, placed in the vicinity of an urban highway (as a source of pollutant production) and were simulated using Computational Fluid Dynamics (CFD). In this research, air velocity and NO 2 concentration were considered as the air quality parameters. Steady 3-dimensional flow was used to simulate these cases using the SST k-[Formula: see text] turbulence model, which was numerically solved based on the Reynolds-averaged Navier–Stokes (RANS) equations. The CFD software used in this research was validated in comparison with wind tunnel tests and acceptable results were found. The TOPSIS multi-criteria decision-making method was used to choose the best case based on increasing the air velocity and decreasing amount of pollutant inside the building. The results show that the best and worst building forms are related to the step-shaped and the L-shaped form, respectively. The results of this research provide design solutions for architects and urban designers to improve the ventilation quality of buildings.