Thermal and fire risk analysis of typical insulation material in a high elevation area: Influence of sidewalls, dimension and pressure
Thermal and fire risk analysis of typical insulation material in a high elevation area: Influence of sidewalls, dimension and pressure
复制标题
DOI：
10.1016/j.enconman.2014.08.026
复制
发表时间：
2014-12-01
影响因子：
10.4
通讯作者：
Liew, K. M.
中科院分区：
文献类型：
--
作者：
An, Weiguang;Wang, Zhe;Liew, K. M.
通过小尺度实验和模型模拟，研究了高海拔城市（拉萨）不同宽度的聚苯乙烯（XPS）平板（有侧壁和无侧壁）上的向下火焰传播特性。本研究提供了在各种因素的影响下，XPS的热特性和火灾危险性的理解。结果发现，火焰脉动是更显着的较宽的样品。平均火焰高度（H）随着宽度的增加而增加。与没有侧壁的结果相比，火焰脉动是不太可观的和H是较高的样品与侧壁。当有侧壁时，平均最高火焰温度（Tmax）随试样宽度的增加而增加，且低于无侧壁时的平均最高火焰温度。侧墙两侧燃烧区的Tmax大于中间燃烧区的Tmax，而无侧墙的燃烧区的Tmax则相反。固相温度曲线由三个阶段组成。在熔化阶段，温度增长速率较低。没有侧壁的熔化阶段的持续时间比有侧壁的长。低海拔地区的持续时间比高海拔地区短。熔化阶段的持续时间越短，对应于熔化阶段发生的温度越高。建立了考虑试样宽度、厚度、环境压力和侧壁影响的三维向下火焰传播模型。用该模型预测的V-f变化趋势与实验结果吻合较好。该模型还可以预测XPS的火灾危险性。XPS的热工及风险分析对建筑节能系统的消防安全设计具有指导意义。(C)2014爱思唯尔有限公司版权所有。
Small-scaled experiments and modeling are performed to investigate the downward flame spread over extruded polystyrene (XPS) slabs at different widths with and without sidewalls in a city (Lhasa, China) at high elevation. This study provides an understanding of the thermal characteristics and fire risk of XPS under the influence of various factors. It is found that the flame pulsation is more significant for wider samples. The average flame height (H) rises as the width increases. Compared to the results obtained without sidewalls, the flame pulsation is less considerable and H is higher for samples with sidewalls. When sidewalls are present, the average maximum flame temperature (T-max) increases with the rise of sample width, and it is lower than that without sidewalls. T-max in the combustion zone besides the sidewalls is larger than that in the middle zone, while the reverse is true for samples without sidewall. The solid-phase temperature curve is comprised of three stages. The temperature growth rate is low during the melting stage. The duration of the melting stage without sidewalls is longer than that with sidewalls. This duration at a low elevation is shorter than that at the high elevation. The shorter duration of the melting stage corresponds to the higher temperature at which the melting stage occurs. A three dimensional downward flame spread model taking into account the effects of sample width, thickness, ambient pressure and sidewall is established. The predicted trends of V-f using the model agree well with the experimental results. The model could also predict XPS fire hazard. The thermal and risk analysis of XPS provides a guidance to fire safety design of energy saving system of buildings. (C) 2014 Elsevier Ltd. All rights reserved.