Explanation of the Interaction of Residential Blocks Layout and the Pollution Dispersal Regarding the Natural Airflow (Case Study: Sobhan Residential Complex, Tehran)

Abstract

Increasingly population and erection of high-rise buildings have multiplied the environmental pollutants in cities. This is while individuals use open urban space more than before to obviate their living requirements. Various factors such as the building layout and the continuous existence of wind can play a significant role in the dispersion of pollutant particles. This study was conducted in this field and its goal was a survey on the impact of high-rise residential buildings layout on the way pollutant particles are dispersed via the cognition of Tehran’s airflow. In this research, the wind behavior around the buildings and pollutant dispersal are analyzed by descriptive-analytical and comparative methods and utilizing the simulation technique with software ENVI-met. The method of information accumulation has been library studies and field research. According to the modeling of the two different types of layout of selected urban block (Sobhan residential complex in Gheytariyeh district, Tehran) with similar building form –one as the existing situation and the other as the proposed model with orderly layout, the findings demonstrate that the layout alternation of residential blocks affects the natural airflow and wind speed between blocks and an improper and non-methodical locating of high-rise buildings causes a change in natural wind pattern and consequently, leads to secondary effects resulted from intensification or stagnation of wind and thus, influences the dispersion of pollutant particles. In this research, the obtained results from the two models of buildings layout in the software and the outputs related to the intensity of wind and the retention level of CO show that the existing situation model is more desirable compared to the proposed layout due to more unified and higher wind speed throughout the site and also proper air circulation between blocks which causes the dispersion of pollution and prevents the retention of pollutant particles.