中庭烟气控制系统研究

发布时间：2018-08-03 08:19

【摘要】：中庭建筑自20世纪80年代被建筑师越来越多地采用，其贯穿性给人们带来美好视觉享受的同时，也使火灾烟气蔓延不受限制，给人民生命财产安全带来巨大威胁。鉴于前人对中庭烟气控制的研究较少考虑环境的影响，本文将对其影响进行分析和研究。 本文介绍了中庭火灾危险性和烟气控制方法，根据文献资料分析归纳了性能化安全疏散指标，并以大空间实验厅为原型，建立建筑模型对中庭烟气行为进行模拟分析和研究。首先，，分析了室内温度对早期火灾烟气上升高度及火灾过程中建筑内温度改变的影响，理论计算表明，30m以下、温度梯度不超过1℃/m的中庭，发生2MW以上功率的火灾，烟羽流通常可以到达顶棚。模拟计算表明，室内温度越高、温度梯度越大，对火灾早期烟气上升的阻碍作用越大。其次，分析了外界风对自然排烟的影响，结果表明，垂直风使较高处烟气温度下降，使较低处烟气温度上升，平行风使中庭内烟气温度整体下降。垂直风速超过3m/s，烟气层下降速度加快。羽流倾斜角度随垂直风速增大而增大，风速为5m/s，羽流严重倾斜，几乎贴近地面。超过一定速度的外界风会降低排烟效率，并使较低位置CO和CO_2浓度减小，却基本不会改变环境中O_2含量，而使能见度条件有明显改善。最后通过工程案例的模拟分析发现，在保证排烟量的前提下，考虑环境条件的影响，采取自然排烟方式亦可以满足人员疏散要求，实现良好的排烟效果。
[Abstract]:Atrium architecture has been used more and more by architects since 1980s. The penetration of atrium architecture not only brings beautiful visual enjoyment to people, but also makes fire smoke spread unrestrained and brings great threat to the safety of people's life and property. In view of the previous research on atrium smoke control less consideration of the impact of the environment, this paper will analyze and study its impact. In this paper, the fire hazard and smoke control methods in atrium are introduced, and the performance-based safety evacuation index is summarized according to the literature data, and the building model is established to simulate and study the smoke behavior in atrium, taking the large space laboratory as the prototype. Firstly, the influence of indoor temperature on the rising height of flue gas and the change of building temperature during early fire is analyzed. The theoretical calculation shows that fire occurs in atrium with temperature gradient below 30 m and temperature gradient less than 1 鈩

本文编号：2161159