隧道竖井高度对高速列车火灾烟气输运特性的影响  

Influence of tunnel shaft height on smoke transport characteristics of high-speed train fires

作　　者：周丹[1,2,3] 唐健瑜 唐子童 ZHOU Dan;TANG Jianyu;TANG Zitong(Key Laboratory of Traffic Safety on Track of Ministry of Education,School of Traffic&Transportation Engineering,Central South University,Changsha 410075,China;Joint International Research Laboratory of Key Technology for Rail Traffic Safety,Central South University,Changsha 410075,China;National&Local Joint Engineering Research Center of Safety Technology for Rail Vehicle,Central South University,Changsha 410075,China)

机构地区：[1]中南大学交通运输工程学院,轨道交通安全教育部重点实验室,湖南长沙410075 [2]中南大学轨道交通安全关键技术国际合作联合实验室,湖南长沙410075 [3]中南大学轨道交通列车安全保障技术国家地方联合工程研究中心,湖南长沙410075

出　　处：《中南大学学报（自然科学版）》2024年第7期2819-2830,共12页Journal of Central South University:Science and Technology

基　　金：湖南省自然科学基金资助项目(2022JJ30744)。

摘　　要：为研究隧道竖井高度对高速列车火灾烟气输运特性的影响规律,采用带有浮力修正的RNG k-ε双方程模型和体积热源模型,构建隧道高速列车运动火灾数值仿真方法,并通过动模型试验验证数值模拟方法的可靠性。研究结果表明:对于着火列车迫停于竖井上游的火灾场景,竖井高度变化对烟气输运特性的影响主要体现在停车后期;列车停车360 s时,随竖井高度增大,竖井烟囱效应增强,隧道拱顶纵向流速正峰值增大,而隧道拱顶温度峰值呈减小趋势。对于着火列车迫停于竖井下游的火灾场景,竖井烟囱效应以及隧道内活塞风对火灾烟气输运起主导作用;列车停车90 s时,烟气出现逆流现象,随着竖井高度增大,火源上游烟气逆流速度峰值增大,烟气逆流长度先增大后保持不变,当竖井高度由20 m增大至100 m时,火源上游高温烟气逆流至竖井底部所需时间缩短253 s;列车停车360 s时,隧道拱顶处温度峰值的变化规律发生改变,当竖井高度由20 m增大至100 m时,隧道拱顶处温度峰值先增大后减小。In order to study the influence of tunnel shaft height on the smoke transport characteristics of high-speed train fires,the RNG k-εequation model with buoyancy correction and the volumetric heat source model were used to construct a numerical simulation method for high-speed train motion fires in tunnels,and the reliability of the numerical simulation method was verified by dynamic model tests.The results show that for a fire scenario where the train is forced to stop upstream of the shaft,the effect of the shaft height change on the smoke transport characteristics is mainly felt in the later stages of the stop.At 360 s of train stop,the positive peak longitudinal flow velocity in the tunnel vault increases with the increase of shaft height,and the shaft chimney effect is stronger,while the peak temperature in the tunnel vault tends to decrease.In fire scenarios where the train is forced to stop downstream of the shaft,the shaft chimney effect and the piston wind in the tunnel play a dominant role in the transport of fire smoke.At 90 s of train stop,the smoke backflow phenomenon occurs.As the shaft height increases,the peak smoke backflow velocity upstream of the fire source increases and the smoke backflow length first increases and then remains constant.When the shaft height increases from 20 m to 100 m,the time taken for the hot flue gases upstream of the fire source to flow back to the bottom of the shaft decreases by 253 s.At 360 s of train stop,the change pattern of the peak temperature at the tunnel vault changes,and as the shaft height increases from 20 m to 100 m,the peak temperature at the tunnel vault first increases and then decreases.

关 键 词：高速列车火灾 隧道竖井 移动火源 烟气输运 

分 类 号：U25[交通运输工程—道路与铁道工程]