中文摘要：

为了解在不同排烟条件下的阴燃机制,对竖直放置在实验体中的聚氨酯泡沫进行阴燃实验研究。在自然对流的条件下,通过改变排烟口的面积研究不同的排烟条件对阴燃的传播过程的影响。用热电偶来测量阴燃过程中材料内部的温度变化,并由此计算出阴燃的传播速度。研究结果表明：当排烟口的面积增大时,阴燃传播过程中的最高温度随之升高,阴燃的传播速度也随排烟口面积的增大而增大。在排烟口完全密闭的情况下,阴燃虽不会向有焰火过渡,但仍可自维持地向上传播,不过传播速度却很慢,持续时间较长。随着排烟口面积的增大,阴燃传播过程中会产生小火苗,炭燃烧的平均升温速率逐渐增大,并且阴燃燃烧后剩余的残炭量逐渐减少。

英文摘要：

In order to understand the mechanism of smoldering of polyurethane foam in different smoke exhaust conditions, smoldering experiments were conducted with vertically-oriented polyurethane foam with natural convection.The effects of smoke exhaust conditions on smoldering propagation were studied by changing the area of the exhaust port.Thermocouples were used to measure the temperature histories inside the polyurethane foam material, and the smolder propagation velocities were obtained from the temperature histories. The results show that the maximum temperature in the smoldering propagation process and the propagation rate increase with the increase of the area of the exhaust port. In the case of the exhaust port fully closed, the smolder propagation doesn＇t transit to flame, but can still sustain itself with low velocity. With the increase of area of the exhaust port, a small flame will appear in the smoldering propagation process, the average heating rate of char burning is gradually increasing, and smoldering combustion residual carbon reduces.