单室火灾的数值模拟研究  

Numerical simulation on fire in a single room

作　　者：刘朝[1] 黎明[1] 

机构地区：[1]重庆大学动力工程学院,重庆400030

出　　处：《消防科学与技术》2006年第5期622-628,共7页Fire Science and Technology

摘　　要：采用大涡模拟和混合分数燃烧模型,对单室火灾进行了数值模拟研究。对混合分数燃烧模型的不足进行了分析,并指出了改进的方向。比较了喷淋和无喷淋状态下单室火灾的烟气发展规律及燃烧产物成分的变化情况。计算结果表明:由于喷淋的加入,可燃物的不完全燃烧性增强,导致烟气中烟灰成分大量增加,二氧化碳等产物的生成量呈减少趋势;对不同燃烧释热率的火灾情况进行了数值模拟,随着火源释热率的增大,室内热烟气的温度增高得更快,热烟气温度层下降的速度越快,下降的高度越低。单室内火灾热烟气的温度分布呈明显的分层现象,可以将场模拟中的烟气层转换为上下两层相互区分的热烟气层和冷烟气层。In this thesis, the single room is simulated numerically and investigated by using Large Eddy Simulation and the mixture-fraction combustion model： （1） The changes of the volume fraction of some products because of burning in the single room with the effect of suppression of water spray or not are compared. The conclusion is that as a result of the effect of suppression of water spray, the fuel close not burn fully, and the volume fraction of soot in the smoke increases while that of carbon dioxide and so on decreases as a consequence. （2） Fires caused by fuel different HRRPUA are simulated. The conclusion is got that： （1） As HRRPUA increasing, the temperature of the hot smoke was raised more quickly. （2） Bigger the HRRPUA was, quicker the falling speed of smoke temperature layer was and lower the falling height was. The temperature distribution of hot smoke showed obvious stratification. （3） This thesis tries to change the thickness of smoke got from the field model into the hot smoke layer which is upon and the cold smoke layer which is below in the room, After all, destruction of fire would be reduced if water sprinklers could work in time and properly.

关 键 词：单室火灾 大涡模拟 混合分数 燃烧模型 热释 放速率 烟 数值模拟 

分 类 号：TK121[动力工程及工程热物理—工程热物理] X924[动力工程及工程热物理—热能工程]