Computational analysis on the performance of smoke exhaust systems in small vestibules of high-rise buildings

[[abstract]]The vestibules in high-rise buildings are specified zones for fire safety. In Taiwan, the designs of the structures and smoke exhaust systems of the vestibules are supervised by different government agencies. The design principles of these smoke exhaust systems take into consideration the flow rates and the impact of the flow momentum. Unfortunately, the current regulations in Taiwan only consider the former. Some small vestibules legally exist in high-rise buildings as they are in compliance with building regulations. This study uses the Fire Dynamics Simulator to analyse 20 modes of smoke exhaust systems under 1.0 MW of the fire load in small vestibules (2 m2 in area). The results indicate that the performance of different smoke exhaust systems significantly varies with different airflow momentums. Some improvement measures are discussed for the worst cases