影响条形走廊排烟效果的因素研究

发布时间：2019-06-05 17:52

【摘要】：火灾的破坏性非常大,它不仅严重地威胁着人的生命安全,还会造成极大的社会财富损失。然而大量资料表明,火灾中对人员产生伤害最大的并不是火源区域,而是流动的烟气。高温烟气不仅含有大量烟尘粒子使人可视距离降低而且还含有有毒或令人窒息的物质,这都将导致人员撤离速度减慢,受到烟气伤害。走廊在建筑中起到连接房间与逃生通道的作用,是人员在火灾中逃生的必经之路。近年来,国内外大量的学者已经对烟气在走廊内的流动特性进行了大量研究。走廊能否有效排烟对人员安全起到了极为重要的作用,因此本文对走廊排烟效果的影响因素进行了一些研究。本文采用火灾动态模拟软件FDS,采用大涡模拟的方法对某职工宿舍楼在自然排烟和机械排烟条件下的排烟进行数值模拟。首先,本文建立了建筑物的计算模型,根据建筑物的特性和模拟需求设置了合适的火源热释放速率和火源位置。然后,研究走廊的自然排烟特性,通过多组工况的计算对比,对走廊自然排烟时开窗形式、开窗位置、室外低温和室外自然风风向、风速对排烟效果产生的影响进行分析。结果表明,除特定风向较高风速外,自然排烟无法满足人员逃生的安全要求。在同样的开窗面积条件下,走廊两端开窗排烟效果好于走廊两侧开窗;外窗高度越高,自然排烟效果越好;风向与走廊方向相同时走廊整体自然排烟效果增强;风向与走廊方向垂直时,对走廊自然排烟产生阻碍。最后,对走廊机械排烟进行模拟和分析。模拟机械排烟时排烟系统参数设定以《高层民用建筑设计防火规范(GB50045-2005)》为基础。文中分别讨论了走廊依靠缝隙补风的不合理性,走廊开外窗的高度、排烟口距离地面高度、排烟口布置数量、排烟口布置位置、排烟量等条件对机械排烟效果的影响。对模拟结果进行分析后得出结论:打开走廊外窗能够保证机械排烟系统的有效运行;机械排烟口距离地面不宜小于3米;走廊外窗高度不宜超过1.6米;本建筑每个防烟分区的合理排烟量是50m3/h。
[Abstract]:Fire is very destructive, it not only seriously threatens the safety of human life, but also causes great loss of social wealth. However, a large number of data show that the greatest damage to people in the fire is not the fire source area, but the flow of smoke. High temperature smoke not only contains a large number of soot particles to reduce the visual distance, but also contains toxic or suffocating substances, which will slow down the evacuation rate of people and be damaged by smoke. The corridor plays the role of connecting the room with the escape passage in the building, and it is the only way for people to escape from the fire. In recent years, a large number of scholars at home and abroad have done a lot of research on the flow characteristics of flue gas in corridors. Whether the corridor can effectively exhaust smoke plays a very important role in the safety of personnel, so this paper studies the influencing factors of the smoke exhaust effect of the corridor. In this paper, the fire dynamic simulation software FDS, is used to simulate the smoke exhaust of a worker dormitory under the condition of natural smoke exhaust and mechanical smoke exhaust by using the method of large vortex simulation. Firstly, the calculation model of the building is established, and the appropriate heat release rate and fire source position are set up according to the characteristics and simulation requirements of the building. Then, the natural smoke exhaust characteristics of the corridor are studied, and the effects of window opening form, window opening position, outdoor low temperature, outdoor natural wind direction and wind speed on the smoke exhaust effect are analyzed through the calculation and comparison of multiple working conditions. The results show that the natural smoke exhaust can not meet the safety requirements of escape except for the specific wind direction and high wind speed. Under the same window opening area, the smoke exhaust effect of window opening at both ends of the corridor is better than that of both sides of the corridor; the higher the height of the outer window, the better the natural smoke exhaust effect, and the better the overall natural smoke exhaust effect of the corridor at the same time as the wind direction and the corridor direction. When the wind direction is perpendicular to the corridor direction, it hinders the natural smoke exhaust in the corridor. Finally, the smoke exhaust of corridor machinery is simulated and analyzed. The parameter setting of smoke exhaust system in simulated mechanical smoke exhaust is based on the Code for Fire Protection of High-rise Civil buildings (GB50045-2005). In this paper, the irrationality of relying on gap air supply in corridor, the height of opening window, the height of smoke outlet from the ground, the number of smoke outlet arrangement, the position of smoke outlet arrangement and the influence of smoke exhaust quantity on the effect of mechanical smoke exhaust are discussed respectively. After analyzing the simulation results, it is concluded that opening the outer window of the corridor can ensure the effective operation of the mechanical smoke exhaust system, the distance of the mechanical smoke outlet should not be less than 3 meters from the ground, and the height of the outer window of the corridor should not exceed 1.6 meters. The reasonable smoke discharge of each smoke prevention zone in this building is 50m ~ 3 / h.
【学位授予单位】：哈尔滨工程大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU834;TU998.1

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