节点文献

地铁岛式站台空气龄及火灾防排烟研究

Study on Air Age and Smoke-Control of Fire at Subway Central-Platform

【作者】 吴文忠

【导师】 由世俊;

【作者基本信息】 天津大学 , 供热、供燃气、通风与空调工程, 2009, 博士

【摘要】 地铁通风系统是地铁工程的重要组成部分,火灾防排烟研究对地铁运营的防灾减灾非常必要。地铁站台是大量乘客的集散地,保持站台良好的空气质量、有效控制站台火灾和烟气一直是地铁运营的难题。本文在天津地铁1号线车站通风系统性能测试和火灾试验的基础上,对地铁岛式站台的空气龄及影响空气龄的因素进行了计算和分析。针对火灾事故,研究了包括纵向送风、火焰图像分析、烟气的波动运动及火灾中的能量转换等有关地铁岛式站台的火灾防排烟的理论问题。本文研究取得的成果包括:提出了站台通风气流运动理论,分析通风气流运动时间及站台空气龄的影响因素,找到降低空气龄的通风措施。利用站台火灾实验的火焰图像,经过图象识别,得到火灾真实燃烧过程的函数式。此函数式表明,这种火灾类型不同于已有的研究成果,从而发展了常用的火灾类型,为进一步应用FDS等软件模拟计算现场温度场、速度场等提供了可靠的依据。当烟气的压力和质量存在幂函数关系时,根据运动守恒方程推导出波动方程,利用它可以预测波动运动,为站台火灾的烟气控制提供了一些新的思路,推广了烟气波的理论解释、传播方程和模拟重构等方面的研究。应用纵向送风控制地铁站台火灾烟气时,可以使火源上游烟气的温度、浓度和空气龄分层,为疏散和灭火提供少烟的区域,节约通风设备的成本和运行中的能源消耗。利用能量转换的观点考察站台火灾,选择有效防排烟方式,降低火灾防排烟的能量消耗,不仅可以保证人员疏散安全和灭火救援方便,同时有利于创造良好的地铁站台环境。

【Abstract】 Ventilation system is a key component of subway station, also study on smoke-control of fire is of much importance for subway safety. During subway travel, so many passengers wait train at and pass by station platform, so concern for good air quality in normal state and safety out of fire at platform is always challenging and difficult.Based on ventilation measurement and fire experiment at stations of Tianjin Subway Line 1, this paper checks affecters of air age, and establishes reasonable ventilation strategies to decrease air age at central-platform. As to fire at station central-platform, this paper works much on theory of smoke-control, including minimal longitudinal ventilation velocity, image analysis to flame of experimental fire, wave motion of smoke, energy transformation in fire, etc. Those results mainly come out with the following:Air flow motion theory is built to analyze motion time of ventilation air flow, find out affecters of air age, then reasonable strategies are used to optimize air flow distribution, decrease air age and obtain better air quality at subway station platform. Analysis to experimental fire images at subway station platform identifies special fire developing process, other than the conventional fire types, and serves to guidelines for calculation of temperature and velocity in FDS etc.When smoke pressure changes with mass of certain power, a kind of linear wave equation for smoke can be derived from the conservation equations. These results make progress in theoretical explanation, propagation equation and simulated reconstruction of smoke wave, and also put forward some new ideas for smoke-control in subway fire environment.Longitudinal ventilation can be activated in subway station platform fire, to stratify temperature, mass rate of smoke and air quality upstream fire source, creating a zone free from smoke for evacuee and fire-fighters, with effective cost and energy.Observe fire and smoke-control strategies in view of energy conversion, select smoke-control mode, further determine whether the energy consumption during subway fire can be reduced, all of which guarantee safety for evacuation, clear room for fire-fighting, and protect environment of subway station platform.

  • 【网络出版投稿人】 天津大学
  • 【网络出版年期】2010年 12期
节点文献中: