中文摘要：

聚氨酯泡沫材料是阴燃火灾中常见的可燃物之一,对变化的聚氨酯泡沫材料的阴燃过程进行了研究.材料变化主要包括连续材料前后部分含水率变化,以及不连续材料前后部分含水率变化.观测各次不同试样试验现象并用热电偶组记录内部的温度变化.结果显示,对于连续材料,当后部含水率小于7.4％时,阴燃稳定传播 后部含水率在10.3％-13.8％时,发生气相反应并形成明火 后部含水率为17.4％时,不能形成明火,后部含水率大于20.9％时,阴燃停止传播.对于不连续材料,在阴燃过程中不易出现明火,当含水率为17.4％时阴燃就会熄灭.材料热分析的TG和DSC数据可清楚显示阴燃反应的各个温度区间和特点.阴燃过程的传热分析也表明,莲续材料比不连续材料更有利于阴燃的传播和明火的形成.

英文摘要：

In this paper, we have done experiments with a variety of kinds of fuel, including continuous samples, some of which are dry while others of which are wet, and discrete samples, also some of which are dry while others of which are wet. The goal of our studies is to find the effect of the discrete moisture-containing materials on the smoldering and the transition from smoldering to flaming combus- tion. As is known, the polyurethane foam is a common fuel in smol- dering fire safety. Our experiments were arranged in a sequence from the dry materials to wet ones when they were smoldering and propa- gating along the samples. We used materials with different moisture contents in different experiments so that we can find different phe- nomena from the different experiments. In addition, we have recorded temperature histories in the smoldering process by using thermocou- pies. For the continuous combustion samples, when the moisture con- tent of the wet part was below 7.4%, the smoldering propagation would be considered steady. However, if the moisture content of the wet part was between 10.3%- 13.8%, the gas-phase reaction would take place and the transition to flaming combustion can be predicted. Furthermore, when the moisture content of the latter wet part reached 17.4%, there would be no flaming combustion appearing at all. Moreover, when the moisture content exceeded 20.9 %, the propaga- tion of smoldering would be slowing down and extinguished. On the other hand, for discrete samples, the transition to flaming combustion would hardly take place at all. Nevertheless, when the moisture con- tent of the latter discrete part reached 17.4%, the smoldering would be extinguished. Thermal analysis experiment of the polyurethane foam let us see that the TG and DSC data could clearly reveal the temperature scopes and characters of smoldering reactions. When the temperature scope remains between 250 - 290 ~C, the reaction of the foam would be endothermic and then would release a lot of com- bustible gas while the TG curve wo