Numerical Simulation of Impacts of Different Types of Air Duct Outlets on Ventilation Efficiency

Abstract:

To enhance the exhaust efficiency during ventilation, three types of air duct outlets were imported. According to the characteristics of velocity distribution simulated by numerical method, the flow field is divided into the mixing zone and the exhaust zone. The gradual contracted air duct outlet can enhance the mixing effect between fresh air and smoke. In the exhaust zone, however, the flow velocity on the upper section of the tunnel is weakened, which is unfavorable for smoke exhaust. Gradual expanded air duct outlet, on the contrary, may weaken the concentration effect of the airflow. The flow velocity on the upper section of the tunnel is increased in the exhaust zone, thus the flow field is more homogenized, which is in favor of smoke exhaust.

• Periodical: Applied Mechanics and Materials (Volumes 438-439)
• Pages: 1098-1103
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.438-439.1098
• Online since: October 2013
• Authors: Chun Zi Nan, Ji Ming Ma, Luo Zhao
• Keywords: Air Duct Outlet, Numerical Study, Tunnel Construction, Ventilation Effect

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