高原和平原环境下宽度对保温材料PS火蔓延特性的影响

Width effect to the flame spread characteristics of the insulation material PS in plateau and plain environments

分别在拉萨高原地区和合肥平原地区开展了一系列保温材料PS(聚苯乙烯)火蔓延对比实验研究,通过对火蔓延过程中一些重要特性参数(火蔓延速度、表面火焰区和池火区火焰高度等)的测量,分析了高原地区和平原地区保温材料PS的火灾危害特性。结果表明,对于同种宽度的EPS或XPS,在拉萨的火蔓延速度均小于在合肥情况下;而当保温材料的宽度为10cm左右时,在两地火蔓延速度均出现了最小值,这主要为空气卷吸程度与热量损失共同作用的结果。研究同样表明,对于EPS和XPS,在宽度比较小的情况下,无论在拉萨还是在合肥,表面火焰区的火焰高度呈现出略大于池火区火焰高度的特点;随着宽度的增加,池火区的火焰高度逐渐大于表面火焰区的火焰高度,并且具有逐渐增高的特性。

A series of comparative experiments were carried out in a small-scale tlame spreaa experimental bench in Lhasa plateau and Hefei plain, respectively and then the fire hazard characteristics of the insulation material of PS was measured in plateau and plain environments by analyzing some important parameters in the process of flame spread of PS （flame spread speed, flame height in the surface flame zone and the pool fire zone）. The re- suits shows that both EPS and XPS, for the same width, the flame spread speed in Lhasa is less than that in Hefei. And when the width of the insulation material of PS was about lOom, the flame spread speed in the two places appears minimum for both EPS and XPS. This was mainly because air entrainment and heat loss both play important role in the process of flame spread. Meanwhile it was found that in the case of relatively small width, both in Lhasa and Hefei, the surface flame height was slightly larger than that in the pool fire zone. With the increase of the width, the flame height in the pool fire zone was gradually greater than the surface flame height, and that has the trend of gradual increase.