国防工程火灾烟气成分分布规律研究

Research on the Distribution of Fire Smoke Composition in Defense Engineering

利用火灾模拟软件FDS,对国防工程发生火灾时不同走廊开口情况下烟气成分在垂直和水平方向上的分布规律进行研究。结果表明:国防工程发生火灾时,单向型走廊内烟气成分在垂直方向上呈上下两层分布,烟气在走廊末端沉降,而在水平方向上烟气成分的分布规律与高度和距火源的距离有关,距火源的距离越远走廊上层O_2浓度越高、CO_2浓度越低,走廊下层正好相反;全封闭型走廊内烟气成分在垂直方向上不会分层,烟气充满走廊,烟气浓度分布受火源燃烧状态影响分为前后两个阶段,前期走廊上层区域烟气浓度会达到极值,后期趋于稳定,而在水平方向上,前期走廊上层区域离火源越远,CO_2浓度越低、O_2浓度越高,后期离火源越远,CO_2浓度越高、O_2浓度越低;烟气迁移及沉降导致远离火源处危险性仍然较高,人员逃生时不可大意。

This paper uses FDS to study the distribution of smoke components in different corridor openingsin the fire protection zone of defense engineering. The results show that in the unidirectional corridors, the smoke distributes vertically in two layers and the smoke settles at the end of the corridors;in the horizontal direction,the distribution law of the smoke components are related to the height and the distance from the fire source. The farther away from the fire source,the higher the O2 concentration and the lower the CO2 concentration in the upper layer of the corridor, and the opposite is true in the lower corridor. The smoke components in the totally enclosed corridors will not be stratified in the vertical direction, and the smoke will fill the corridor. The distribution of the smoke concentration affected by the burning state of the fire source can be divided into two stages. The concentration in the upper area will reach the extreme value in the earlier stage and will stabilize in the later stage;in the horizontal direction,the farther the upper zone of the corridors from the fire source in the earlier stage,the lower the CO2 concentration and the higher the 02 concentration,while the farther away from the fire source in the later stage, the higher the CO2 concentra tion and the lower the CO2 concentration. The smoke migration and settlement result in a higher risk of fumes away from the source of the fire,and the feature must be taken into account when a person flees.