城市交通隧道内火灾环境发展规律的数值模拟研究

为缓解城市地面交通压力,城市交通隧道在许多大城市中已经得到越来越多的应用。由于城市交通隧道具有特殊的交通特性、地理位置及建筑结构,其火灾安全问题受到了极大的关注。研究其内部的火灾环境,对于设置相应的防火安全设施来保证内部人员和隧道结构本身的安全至关重要。本文采用数值模拟的手段,对自然通风工况下,有坡度和无坡度隧道在火灾环境下的温度分布特性进行了研究。研究结果表明,2种隧道内的温度分布特性有很大差异;对于由烟囱效应导致的有坡度情况下的温度分布特殊性,在制定相应的防排烟措施时应充分考虑。研究结果对于隧道的结构防火设计、防排烟系统设计及火灾时的人员疏散方案制定有一定的参考价值。

Numerical Studies on Development Law of Fire Environment in Urban Traffic Tunnel

More and more urban traffic tunnels are built to mitigate the traffic problems in many large cities in China at present time.Fire safety problems are more important due to the large daily traffic flow,special locations and building structures in these kinds of tunnels.To understand the fire environment is a key point for the fire prevention system design.Numerical studies on the fire environment in tunnels with or without slope were carried out by software FDS in this paper.Longitudinal temperature distributions were obtained.Different fire behaviors were found for the fires occurring in the tunnels with and without slope. The results show that due to the stack effect,the temperature fields in a slope tunnel are not symmetry, hot smoke spreads towards the top exit,and the spread speed is much faster than that in the normal tunnel. This might be dangerous for the passenger's evacuation.Special measures should be taken for these kinds of fire conditions.