棉花阴燃和明火燃烧特性的对比研究

利用锥形量热仪,选取不同辐射强度,分别在使用和不使用点火器条件下,对棉花进行了热辐射引燃实验,发现在热辐射强度大于6kW/m2的情况下,使用点火器时棉花发生明火燃烧,不使用点火器时棉花发生阴燃燃烧。实验分别测得了在两种燃烧形式下的引燃时间、热释放速率、质量损失速率一氧化碳生成率,结果表明:无论是发生阴燃还是明火燃烧,引燃时间均随着辐射强度的增加而减小,且引燃时间平方根的倒数与辐射强度成线性关系;热释放速率、质量损失速率的峰值和平均值均随辐射强度的增加而增加,但在同一辐射强度下,明火燃烧的峰值和均值均比阴燃燃烧时的大;明火燃烧的一氧化碳平均生成率随着辐射强度的增加而减小,阴燃燃烧的一氧化碳平均生成率随着辐射强度的增加而增加。

A comparative study on the characteristic of cotton smoldering and flaming combustion

The pilot and spontaneous ignition experiments of cotton were conducted in cone calorimeter under different external heat radiation intensities. With the heat radiation intensity being greater than 6 kW/m2, the flaming combustion of cotton was observed when the igniter was used, while only smoldering was observed when the igniter was not used. The time to ignition, heat release rate, mass loss rate and carbon monoxide producing rate were measured. The experimental results revealed that no matter smoldering or flaming combustion, the ignition time decreased with the increasing of heat radiation intensity and the reciprocal square root of the ignition time depended linearly on the heat radiation intensity; the peak value of heat release rate and mass loss rate increased with the heat radiation intensity. While under the same external heat radiation intensity, the peak and mean values of smoldering were greater than flaming combustion, the mean value of carbon monoxide producing rate in smoldering increased with the heat radiation intensity, while it decreased in flaming combustion.