摘要
为研究火源间距对隧道内双火源燃烧特性的影响,本文开展小尺寸模型隧道火灾实验,研究不同间距下,空气卷吸与辐射热反馈的竞争关系对火源质量损失规律和顶棚温度变化规律的影响;分析远火源区顶棚温度的分布规律,并采用数值模拟方法进行验证。结果表明:火源间距在10~15 cm之间增大时,空气卷吸作用占主导地位,卷吸受限导致火源质量损失速率下降,顶棚最高温度也因此有所下降;当火源间距大于15 cm时,空气卷吸充足,辐射热反馈发挥主要作用。远火源区顶棚温度分布规律不受间距变化影响,始终满足指数衰减,且与数值模拟结果吻合良好;相较初期发展阶段,不同间距对充分发展阶段的远火源区顶棚温度纵向衰减快慢影响较大。
In order to study the influence of fire spacing on the combustion phenomenon of two fire sources in tunnel,this paper carried out small-scale model experiments for tunnel fire to study the effects of competition between air entrainment and radiant heat feedback on the mass loss law of fire sources and the variation law of ceiling temperature.The distribution law of ceiling temperature in the far field is analyzed,and is verified by numerical simulation method.The results show that when the spacing of fire sources increases between 10-15 cm,air entrainment is dominant.The mass loss rate of fire sources decreases due to restricted entrainment,and the maximum temperature of the ceiling also decreases.When the spacing of fire sources is greater than 15 cm,air entrainment is sufficient,and radiant heat feedback plays a major role.The temperature distribution law of the ceiling in the far field is not affected by the variation of the spacings,and always satisfies the exponential decay,and has a good agreement with the numerical simulation results.Compared with the initial development stage,different spacings have a greater impact on the longitudinal attenuation of the ceiling temperature in the far field at the full development stage.
作者
徐浩祯
赵威风
吕思嘉
XU Hao-Zhen;ZHAO Wei-Feng;Lü Si-Jia(School of Rail Transportation,Soochow University,Suzhou 215131,China;Hefei 230027,China)
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2020年第5期1254-1260,共7页
Journal of Engineering Thermophysics
基金
国家自然科学基金项目(No.51506136)
中国科学技术大学火灾科学国家重点实验室开放课题(No.HZ2018-KF05)。
关键词
隧道火灾
双火源
质量损失
温度分布
数值模拟
tunnel fire
double fire sources
mass loss
temperature distribution
numerical simulation
