摘要
采用FDS对单室火灾中细水雾与火焰相互作用过程进行数值模拟分析,探讨细水雾与火焰相互作用过程中不同区域的细水雾灭火机理,分析粒径分布、速度和雾化角度对细水雾灭火产生的影响。模拟结果表明:在细水雾与火焰相互作用过程中粒径分布对灭火效能影响显著;细水雾在粒径小于100μm时不能实现有效灭火;当粒径为200～400μm时细水雾能有效抑制火焰发展并熄灭火源;在细水雾灭火机理中,相对于气相冷却和隔氧窒息,细水雾的表面冷却作用起到主导作用;细水雾喷射速度对灭火效果影响较大,细水雾动量不小于火羽流动量是火灾发展得到有效控制的重要前提;细水雾有效雾通量随着雾化角度增大而逐渐减小,雾化角度增大不利于细水雾灭火效能提高。
A numerical simulation with FDS was carried out for the interaction of water mist with pool fire. The extinguishing mechanism of water mist in different regions of fire plume and the influences of particle size distribution, velocity, spray angle were investigated. The results showed that particle size distri- bution had a great effect on fire extinguishment. When the droplet diameters were 100μm,the fire cannot be extinguished; when droplet diameters were in the range of 200-400μm, the fire was suppressed by water mist effectively and extinguished finally. In the extinguishing mechanisms, the surface cooling effect played a more important role than the gas-phase cooling effect and suffocation effect; At the same time, the velocity of the droplet also had a great effect on the effectiveness of fire extinguish; an important prerequisite for the fire extinguishment was that the water mist momentum should not be less than the fire＇s momentum;The water mist flux became smaller withthe increase of spray angle, the increase of spray angle wasn＇t conducive to fire extinguishment.
出处
《消防科学与技术》
CAS
北大核心
2012年第3期275-278,共4页
Fire Science and Technology
关键词
细水雾
灭火效能
FDS
数值模拟
water mist
extinguishing efficiency
FDS
numerical simulation
