中文摘要：

聚氨酯泡沫材料是阴燃火灾中的典型可燃物之一.在实验台上进行了自然对流条件下通风面积变化的阴燃实验,利用热电偶测量材料内部温度变化,用气体分析仪测量所产生的CO浓度.结果显示,对于横截面积为408×10-4 m2的泡沫材料,当通风面积与材料横截面积之比r小于1/260时阴燃会熄灭,r〉1/260时阴燃会最终转化为明火.由此确定该数值是阴燃维持的临界通风面积.通过不同通风面积情况下生成的CO量的对比,发现在r=1/260时生成的CO明显增多,说明在形成明火后,由于空气供应受限,会大量产生CO.

英文摘要：

The polyurethane foam is one of the typical fuels in smoldering fire. Experiments were conducted under the condition of natural convection by varying the ventilation area. The thermocouples were used to measure the temperature histories inside the material, and a gas analyzer to measure the concentration of CO. The results show that, for the polyurethane foam with a section area of 408 N 10-4 m2, smoldering will extinguish when the ratio of ventilation area and foam section area is less than 1/260, and will lastly transfer to flaming when the ratio is larger than 1/260. Thus, this value can be considered as the critical condition for maintaining smoldering. A comparison of generated CO volumes at different ventilation areas reveals a significant increase of CO under the ratio equaling 1/260. In the case of transition from smoldering to flaming, a large amount of CO will be generated when the air supply is limited.