Abstract:

Fluent was used to analyze the uniform exhaust generated by the adjustment of the 45° built-in regulating valve at the rail-top hot air outlets of the 6-section and 8-section subway stations and the coordinated smoke exhaust effect under the platform fire condition. The research results showed that the exhaust air volume of the rail-top heat exhaust system increases with the increase of exhaust air pressure after the two types of stations are adjusted by the regulating valve at the rail-top hot exhaust outlet. The total exhaust air volume formed by the regulating valve at the rail-top hot air outlet is higher than that formed by the flapper valve under the same exhaust pressure.When the regulating valve is used, the unbalance rate between the outlet can be kept within 5%, which can realize uniform air exhaust.While the unbalance rate of the outlet is more than 20% when the flapper valve is used, and the balance of the air volume between the outlet cannot be achieved. When a fire occurs on the platform of the two types of stations, by the rail-top uniform heat removal system with regulating valve, each stairway of the station platform can form the blocking air flow that is not less than 1.5m/s to prevent the smoke from spreading upwards, the air volume at the exhaust outlet on the top side of the rail does not exceed the maximum allowable smoke exhaust, which meets the relevant requirements of the specification. Cooperative platform fire smoke exhaust program is effective and feasible.

Key words:  , rail-top heat exhaust system, unbalance rate, uniform exhaust, rail-top side smoke outlet, cooperative smoke exhaust