灭火添加剂对细水雾性质与灭火效能的影响

Effect of Additives on Characteristics and Fire Suppressing Efficiency of Water Mists

为了提高细水雾的灭火效能,研究了两种复合细水雾灭火添加剂G1和G2对水的物理化学性质的影响.通过试验研究了G1和G2对水溶液密度、黏度、表面张力、细水雾粒径分布以及灭火效能的影响.结果表明,G1和G2对水溶液的密度和黏度影响不大,G1使水溶液的表面张力和细水雾的雾滴粒径减小,G2使水溶液的表面张力和细水雾的雾滴粒径增大.通过清水细水雾和含G1和G2的细水雾熄灭煤油池火的试验,得到灭火效能的顺序:含G1细水雾>含G2细水雾>清水细水雾.分析了含G1和G2的细水雾对煤油池火的抑制熄灭机制,G1和G2中各成分之间的偶合效应提高了细水雾的综合灭火效能,含有G1的细水雾主要是通过提高细水雾蒸发吸热降温效果及气相俘获自由基的作用来提高灭火效能,而含有G2的细水雾主要通过提高大粒径雾滴穿透火羽流,冷却燃烧物表面及气相俘获自由基的作用提高灭火效能.

In order to improve the efficiency of plain water mist, the influence of two additives G1 and G2 on physical and chemical property of water was investigated. On the basis of suppression mechanisms of plain and additives-containing water mist, density of water-additives solution, viscosity, surface tension, diameter of water mists and fire suppression efficiency of water mist with additives G1 and G2 were experimentally examined. Additives G1 and G2 have little effect on the density and viscosity of the solution. Additive G1 reduced surface tension and diameter of water mist, while additive G2 increased surface tension and diameter of water mists. Suppression tests on kerosene pool fire showed that the order of suppression effectiveness is G1 〉 G2 〉 plain water mist. The coupled effect among various components of additives could enhance fire suppression efficiency of water mist. Water mist with G1 mainly enhanced fire suppression effectiveness by increasing evaporation process and radical capture, and the improved effectiveness in mist with G2 is mainly due to enhanced fuel surface cooling induced by high penetration into flame plume of water mist with a larger diameter and flame radical capture.