聚氨酯泡沫材料密度对阴燃及向明火转化过程的影响

为了探讨材料参数对阴燃及向明火转化过程的影响,对水平放置在实验体中4种不同密度的聚氨酯泡沫进行阴燃实验研究,并选取2种典型密度材科利用气相色谱仪对气体产物进行分析,结合热分析研究材料密度对阴燃及向明火转化过程的影响机理.研究结果表明:在自然对流条件下,密度大的聚氨酯泡沫材料,反应产生的热量多.此外,密度大的聚氨酯泡沫在阴燃过程中产生较高浓度的CO气体,可提供充足的可燃气体,故更容易由阴燃向明火转化:而对于密度小的聚氨酯泡沫,在阴燃过程中产生的CO,CO2气体的量和消耗的O2的量变化小,放出的热量也较少,所以仅可以维持稳定的阴燃传播.材料密度对阴燃及向明火转化的过程有重要影响,实验结果对防止火灾事故的发生具有一定的现实意义.

Effect of sample density on smoldering and transition to flaming combustion

In order to understand how the material parameters take effects on smoldering and transition from smoldering to flaming combustion,four kinds of different density polyurethane foams and analysis gaseous products were studied with gas chromatograph.Combined with thermal analysis,the influence of material density to smoldering and transition from smoldering to flaming combustion was discussed.The results show that polyurethane foam which has the big density produces more calories in natural and produces high concentrations of CO,and provides plenty of flammable gas.So,it is easier to promote the transition form smoldering to flaming combustion.The polyurethane foam which has the small density produces little CO,CO2,and consumption little O2,and releases less heat in smoldering process.So it only can maintain stable smoldering spread.Therefore,the research on smoldering and transition from smoldering to flaming combustion can play a practically significant role in fire prevention.