Evaluating factors affecting wind ventilation performance inside pedestrian zone located within dense residential estates in Hong Kong

Wind ventilation performance within high rise residential estates is important because it affects thermal comfort of pedestrians, indoor and outdoor air quality, and energy consumption in domestic sector. For effective utilization of natural ventilation, research and references in this area are highly needed. This paper presents a comparison of the wind ventilation performance of three typical residential estates in Hong Kong. Computational Fluid Dynamics (CFD) software was used to simulate the airflow distribution around buildings. The influence of the dense high-rise buildings on ventilation performance expressed in velocity ratio was found to vary with estate layouts and building forms. It was found that the estate with building blocks evenly scattered and the gaps parallel to the prevailing wind directions was better performed. A sensitivity analysis on the influence of various factors affecting the wind ventilation performance, namely: the building height, the windward building width and the distance between building blocks, was conducted. The results indicated that wind ventilation performance was most affected by the building height, thereafter were the distance between building blocks, and the windward building width.