FDS (Fire Dynamics Simulator) was applied to simulate the vertical combustion of external wall thermal insulation material in this article. Firstly the parameters of EPS, XPS and PU were designated according to engineering preference and the fire source was provided by the window fire. After the simulating, those data were sorted. It was found that the height of flame changed in the form of nonlinear change: y = at2 + bt + c. The shape of trend line was a parabolic. The height of flame changed quickly in the earlier stage of simulating wih the later stage changing slowly. The velocity of flame front changed in the form of linear change:vp=αt + β. The velocity of flame front reduced stably in the simulating. XPS had the best thermal conductivity, so the temperature in each test point rised the most slowly. The EPS' temperature variation curve was the most stable in all with the best coefficient of thermal storage. The conclusion can provide certain prediction for the vertical combustion of actual external wall insulation material on the constructions and improve the efficiency of fire fighting and rescue for the fire department.%根据外墙保温材料具体的工程参数为依据,对挤塑型聚苯乙烯(XPS)、膨胀型聚苯乙烯(EPS)和聚氨酯(PU)三种材料的燃烧参数进行设定,设定火源为从窗口喷射而出的火焰,运用FDS软件进行数值模拟与分析.经过模拟发现:外墙保温材料在竖向燃烧中,火焰前锋高度呈现抛物线式增长,y=at2+bt+c,前期增长迅速,后期逐渐平稳.火焰前锋速度按照线性变化,vp=αt+β.在整个燃烧过程中,火焰前锋速度平稳的降低.XPS板导热系数最好,各测点的温度上升最慢,EPS板蓄热系数最好,所以其温度曲线最为平稳.
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