摘要
在高原环境(低压低氧)的拉萨和平原环境(常压常氧)的合肥,研究了不同宽度(W=4,8,12,16cm)的保温材料在不同放置角度(0°,15°,30°,90°)下的火焰结构及火蔓延特征.结果表明,外界环境对火焰角度、池火长度、火蔓延速度(vf)均有影响,相同放置角度下相同宽度的模塑聚苯乙烯泡沫板(EPS)和挤塑聚苯乙烯泡沫板(XPS)试样在拉萨的火焰角度均大于合肥;燃烧剧烈的XPS对火焰角度的影响明显高于EPS,池火长度随材料宽度及放置角度不同呈现分段递增、逐渐增长、流淌滴落等特点;在拉萨试样更易出现二次点燃现象;无论在拉萨还是合肥,90°放置角度下,EPS和XPS试样vf均随材料宽度增加呈先增加后减小的特点,火蔓延过程中火焰辐射热通量受宽度影响,宽度较小时vf遵循vf∝1-e-kW,宽度较大时遵循vf∝Th4.
The flame structure and spread characteristics of insulation materials expandable polystyrene （EPS） and extruded polystyrene （XPS） with the widths （W） of 4, 8, 12 and 16 cm inclined at the angles of 0°, 15°, 30° and 90° in the typical environments of Lhasa （low pressure and oxygen content） and Hefei （normal pressure and oxygen content） were studied. The result shows that the environments affect the flame angle, pool fire length and flame spread speed （vf）. For the same width of EPS and XPS inclined at the same angle, the flame angle in Lhasa is bigger than that in Hefei, and it is more influenced by XPS than EPS for the more intensive combustion. The pool fire shows the cyclical increasing and the continual increasing in the length, and has the flowing and dripping characteristics when the width and inclined angle are changed. In Lhasa, the surface flame is easier to extinguish and then the surface zone is ignited again. When EPS and XPS are inclined at the angle of 90° in Lhasa and Hefei, vf firstly decreases with the width of sample and then increases, for the radiative heat flux dominates the whole process. When the width is relatively small, vf follows vf∝1-e^-kw, while when the width is large, it follows that vf∝Th4.
出处
《过程工程学报》
CAS
CSCD
北大核心
2013年第2期345-350,共6页
The Chinese Journal of Process Engineering
基金
国家重点基础研究发展计划(973)基金资助项目(编号:2012CB719700)
国家自然科学基金资助项目(编号:51206002)
火灾科学国家重点实验室开放基金资助项目(编号:HZ2012-KF04)
