隧道路面横坡对流淌火燃烧蔓延规律影响的实验研究
Experimental study on influence of ground transverse slope on combustion and spread law of spill fire in tunnel
吴博文 1陈长坤 1焦伟冰 1林子达1
作者信息
- 1. 中南大学土木工程学院,湖南长沙 410075
- 折叠
摘要
为探究地面横坡对隧道流淌火燃烧蔓延规律和温度场分布特征的影响,搭建缩尺寸隧道模型开展研究.研究结果表明:当泄漏速率较小时,有横坡的隧道流淌火的燃烧扩散可分为4个阶段,分别为燃烧横向扩散阶段、回缩阶段、燃烧稳定阶段以及熄灭阶段;当泄漏速率较小时,流淌火仅存在横向扩散阶段,而当泄漏速率较大时,在燃料横向扩散阶段之后会形成贴壁纵向扩散,进而形成隧道内的"T型火".通过理论分析建立相应的流淌火横向扩散距离以及纵向扩散距离的理论预测模型.此外,当泄漏速率较小时,隧道顶棚高温区域在隧道中心.当形成"T型火"时,火焰贴壁一侧的温度明显高于隧道中心线温度.研究结果可为隧道流淌火火灾的探测设计提供理论支撑.
Abstract
In order to investigate the influence of ground transverse slope on the combustion and spread law and the tempera-ture field distribution characteristics of spill fire in tunnel,a reduced-size tunnel model was constructed to carry out the study.The results show that when the leakage rate is small,the combustion diffusion of spill fire in tunnel with transverse slope can be divided into four stages,which are the combustion transverse diffusion stage,the retraction stage,the combustion stabiliza-tion stage,and the extinguishing stage.When the leakage rate is smaller,there is only a transverse diffusion stage of the spill fire,and when the leakage rate is larger,the longitudinal diffusion adhering to the wall will be formed after the transverse dif-fusion stage of fuel,thus forming the"T-shape fire"in the tunnel.Through theoretical analysis,the corresponding theoretical prediction models of transverse diffusion distance and longitudinal diffusion distance of spill fire are established.In addition,when the leakage rate is small,the high temperature region of the tunnel roof is in the center of the tunnel.When a"T-shaped fire"is formed,the temperature on the wall side of flame is significantly higher than the temperature at the centerline of tun-nel.The research results can provide theoretical support for the detection design of spill fire in tunnels.
关键词
隧道流淌火/横坡/泄漏速率/燃烧速率/温度场Key words
spill fire in tunnel/transverse slope/leakage rate/combustion rate/temperature field引用本文复制引用
出版年
2024
NETL
NSTL
万方数据