细水雾抑制熄灭木材火焰的小尺度实验研究及简化模型

细水雾灭火技术以其环保性好、灭火迅速、耗水量低、破坏性小以及适用面宽等特点 ,已成为国际火灾领域关注研究的热点。以此为工程背景 ,开展了细水雾抑制熄灭木材火焰的小尺度模拟实验研究。利用热电偶测温系统、数码摄像机等仪器测量了细水雾作用前后燃烧场的变化特征。结果表明 :预燃时间、喷雾气压、细水雾作用时间等参数对灭火过程有显著影响。细水雾抑制熄灭木材火焰的主要机理是燃料表面冷却效应。从传热的角度建立的木材表面冷却模型与实验结果吻合较好

Pilot Experiment and Simplified Model for Inhibition of Fading Wood Fire by Water Mist

The advantages of water suppression technology, including environment benefit, fast extinguishment, low water consumption, and wide practicability,have received considerable attention in international fire science research field. A pilot experiment for observing the interaction of water mist with fading wood fire was conducted. Thermocouples and digital video were used to measure the characteristic parameters of the burning area. The experiment indicated that the pre-burning time, pressure for forming the water mist, and the interaction time significantly affected the course of extinguishment. The main mechanism of extinguishment was the surface cooling effect. A simplified theoretical model for surface cooling effect was developed based on heat transfer theory, and the calculated values were in good agreement with the experimental results.