改性干水灭火剂灭木垛火试验研究

新型干水灭火剂因其高含水量和特殊核壳结构，具有良好的灭火效果。为探究干水对木垛火的灭火效果，自行制备磷酸二氢铵改性干水并开展小尺寸木垛火灭火试验。结果表明：干水灭火剂能够扑灭小尺寸木垛火且不发生复燃，改性干水的控火时间仅为8 s，控火过程中火焰高度持续快速下降，而干粉灭火剂的控火时间则为20 s，喷撒结束39 s后发生复燃；改性干水对火焰区及木垛的温度抑制效果均优于干粉灭火剂，控火时间内，改性干水作用下木垛表面的平均温降速率高达17.00℃/s，是干粉灭火剂作用下平均温降速率的1.94倍；改性干水能够有效降低木垛内部温度，在喷撒50 s内，木垛中心的平均温降速率为8.78℃/s，而干粉灭火剂缺乏冷却作用，木垛中心的平均温降速率仅为6.10℃/s，无法有效抑制阴燃。

Experimental study on wood crib fire with modified dry water extinguishing agent

The new-type dry water fire extinguishing agent has a good fire extinguishing effect due to its high water content and special core-shell structure. In order to explore the fire extinguishing effect of dry water on wood crib fires, the modified dry water was prepared by adding ammonium dihydrogen phosphate and carried out small-scale wood crib fire extinguishing experiments. The results show that the dry water fire extinguishing agent can extinguish the fire without re-ignition, the fire control time of the modified dry water is only 8 s, and the flame height continues to drop rapidly during the fire control process, while the fire control time of the dry powder is 20 s, and re-ignition occurred 39 s after spraying. The temperature suppression effect of the modified dry water on the flame area and the wood crib was better than that of the dry powder. The average temperature drop rate is as high as 17.00 ℃/s, which is 1.94 times the average temperature drop rate under the action of dry powderduring fire control time. The modified dry water can effectively reduce the internal temperature of the wood crib, the average temperature drop rate in the center of the wood crib is 8.78 ℃/s during within 50 s of spraying, while the dry powder lacks cooling effect, and the average temperature drop rate in the center of the wood crib is only 6.10 ℃/s, which cannot effectively suppress smoldering.