impact of balcony depth and position on indoor air quality of apartments located along urban traffic corridors

Today, traffic-related pollution in cities has become a fundamental problem, especially in large urban areas. balcony characteristics, including shape, depth, length, height of the parapet, balcony position, and so on, have different effects on ventilation quality and the concentration of pollutants entering the building. this study evaluates the role of two variables, balcony depth and its placement, on indoor air quality. for this purpose, 12 buildings with different balcony depths and placements near a metropolitan highway were chosen as case studies and simulated using cfd. the balcony placement in the case studies includes three balcony patterns: facing the prevailing wind, facing away from the prevailing wind, and on both faces; in each pattern, four depths from 0.5 meters to 2 meters were considered for the balconies. this study employs three-dimensional steady rans equations combined with the k-ω turbulence model to solve the equations. the results show that balconies generally reduce both wind speed and the ingress of pollutants into the indoor space compared with buildings without balconies; however, increasing balcony depth on the windward side decreases the incoming wind speed but increases the concentration of pollutants entering the building. therefore, changes in balcony depth within this range have little effect on airflow speed or pollutant concentration entering the building; ultimately, employing balconies on both the windward and leeward sides markedly reduce wind speed and pollutant concentrations entering the building, and increasing balcony depth on this side decreases the incoming wind speed while increasing the pollutant concentration entering the building.