Field Measurement and Numerical Simulation of the Relationship Between Vertical Wind Environment and Building Morphology in Residential Areas in Xi’an, China

Abstract The inadequate consideration of the impact of building morphology on ventilation efficiency in many urban residential areas has resulted in a series of environmental problems that threaten human health. The purpose of this paper is to establish a prediction model between ventilation efficiency and building forms in residential areas. Firstly, the characteristics of vertical wind profile in residential areas are measured through unmanned aerial vehicle (UAV); secondly, the wind speed ratio (WSR) at different height levels under the impact of morphological index (floor area ratio, building density, average building height, enclosure degree, height fall and maximum building height) in the residential area is simulated by ENVI-met; finally, two kinds of prediction formulas are obtained: (1) the average ventilation efficiency at the pedestrian level and (2) the prediction formula of WSR at different heights. The results show that the wind speed (WS) in residential area below 35 m is about 0.6 m/s lower than that in park. The results of numerical simulation show that the mean WSR at the pedestrian level is negatively correlated with each index and the height fall morphological index has the greatest impact on the WSR at different heights. The research can provide a reference for the optimal planning and design of ventilation efficiency of residential buildings, especially those in static wind areas.