Experimental Study on Smoke Exhaust Effect by Using Jet Fans in an Underground Garage

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Construction Engineering Volume 4, 2016 www.seipub.org/ce doi: 10.14355/ce.2016.04.004

Experimental Study on Smoke Exhaust Effect by Using Jet Fans in an Underground Garage Ren Zhang, Yanfeng Li, Lin Chang, Qiang Liang College of Architectural and Civil Engineering, Beijing University of Technology, Beijing, 100124 liyanfeng@emails.bjut.edu.cn Abstract In order to research the technical feasibility and influence factors of impulse ventilation systems in an underground garage, full‐scale fire tests have been designed and conducted. Four testing conditions have been designed by changing jet fan combination form and opening time. The temperature and smoke layer at different distances from the fire source have been recorded. Results show that jet fan would drive smoke to the downstream exhaust port more quickly and visibility of fire source upstream would be increased. There is a significant change on smoke exhaust of jet fan combination. Series arrangement of jet fan would keep smoke layer temperature stable and smoke could be exhausted effectively. However, series‐parallel combination of jet fans could cause a high fluctuation in smoke layer temperature. It would do harm to exhaust smoke quickly in garage. Key word Underground Garage; Jet Fan; Smoke Exhaust; Impulse Ventilation

Introduction Underground garage is a low‐rise space. Garage is characterized by a low floor height, a lot of wires and a very large area. There are dangers in fire safety. Test results show that garage fire is rapid‐velocity combustion, high temperature smoke, low visibility. Buildings above the garage will be damaged by the fire because of explosion [1‐3]. More and more underground garage install no duct induction ventilation exhaust system because of tradition ventilation on exhaust system’s weakness. Smoke exhaust mode needs to consider the smoke layer disturbance, subsidence, human evacuation, organization of the flow field and other factors. Preliminary studies at home and abroad have focused on major underground garage induction ventilation exhaust system. No systematic research on induced fan flow field characteristics and influence of space structure on induced smoke exhaust [4‐6]. The paper has been designed and conducted full‐scale fire tests in underground garage. Four testing conditions have been designed by changing jet fan combination form and opening time. Texts measurements on the temperature up‐downstream fire source, to observe changes in smoke layer. Provide a theoretical basis for the study of the impact of induced ventilation on heat release rate, research and analysis of dynamic characteristics of fire, distribution Characteristics of induced smoke layer [7‐10]. Field Test Conditions of Underground Garage Induced Ventilation

FIG.1 SCHEMATIC DIAGRAM OF UNDERGRROUND GARAGE FIELD TEXT

The test site is an underground double garage in Tianjin. The size of garage is 67m (length) X25.4m (width) X4.2m (Height). The garage is divided into a smoke control area. Garage exhaust system with using ducted exhaust has

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Experimental Study on Smoke Exhaust Effect by Using Jet Fans in an Underground Garage by Shirley Wang - Issuu