An investigation on ventilation potential as a result of the provision of series of balconies on high-rise residential buildings using computational fluid dynamics (CFD)

The trend of urban residential buildings to be built vertically due to site optimization and demand for residential units, results in greater potential to harvest the prevailing wind to improve indoor ventilation performance through passive design strategies, and consequently to reduce energy consumption of the buildings. Indoor ventilation performance in buildings is dependent on various factors, particularly the characteristics of façade relief such as balconies commonly found in high-rise residential buildings. While the balcony is adopted to serve various purposes, it is essential to examine the balcony in the context of ventilation studies, since it could significantly influence outdoor and indoor airflows characteristics. This paper explores the ventilation performance impacts of providing balconies on the facades of a high-rise residential building, using Computational Fluid Dynamics (CFD), a powerful tool which has recently changed how researchers conduct outdoor and indoor airflows studies for buildings. The first objective of this study is to investigate through literature review the potential of CFD models in comparison to other ventilation prediction models. The second objective is to analyze the ventilation performance of apartments in relation to their vertical distances from ground level and the provision of balconies on the façades. This study found that while the CFD application is accurate and able to provide comprehensive data, it is difficult to assess and requires validation and high computation time. In regard to ventilation performance, this study confirmed that apartments located at higher positions have greater ventilation potential due to higher wind speed, however it also found that the ventilation performance for each residential unit is very site specific and the provision of series of balconies could contribute positively or negatively to indoor ventilation performance.