基于全尺寸实验的高铁隧道火灾烟气纵向流场特征研究  

Full-scale experimental study on longitudinal smoke flow field characteristics in high-speed railway tunnels

作　　者：潘荣亮 王亚南 岳顺禹 冉辰皓 程辉航 钟茂华 PAN Rongliang;WANG Yanan;YUE Shunyu;RAN Chenhao;CHENG Huihang;ZHONG Maohua(Institute of Public Safety Research,Department of Engineering Physics,Tsinghua University,Beijing 100084,China;School of Safety Science,Tsinghua University,Beijing 100084,China;China Railway Seventh Group Co.Ltd.,Wuhan 430200,China)

机构地区：[1]清华大学工程物理系,公共安全研究院,北京100084 [2]清华大学安全科学学院,北京100084 [3]中铁七局集团武汉公司有限公司,武汉430200

出　　处：《清华大学学报（自然科学版）》2024年第9期1575-1586,共12页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金面上项目(52374210);国家自然科学基金青年科学基金项目(52304234)。

摘　　要：中国高铁隧道具有明显的高拱顶、大断面特点,为研究上述特征作用下高铁隧道火灾烟气纵向流动与温度分布特征,该文依托渝湘高铁重庆至黔江段的白家山隧道开展了全尺寸高铁隧道火灾实验,获取了火灾烟气在纵向方向上的蔓延速度与温度分布特征。研究发现:尽管高铁隧道净高、横截面积较常规公路隧道变大,高铁隧道火源热释放速率对烟气纵向蔓延的速度仍然起到重要作用。高铁隧道内火灾烟气温度在垂直方向上呈现出经典的“top-hat”分布,并且随着烟气远离火源位置,烟气垂直方向温度的“top-hat”分布特征逐渐趋于一致。此外,该文划定了高铁隧道热烟气纵向流动的一维过渡射流区(区域II)与一维临界射流区(区域III)分界线,探究了现有狭长受限空间内火灾烟气纵向流动与温度分布模型在高铁隧道火灾领域的适用性并分析误差原因,调整了适用于高铁隧道射流区域III的热烟气温升纵向衰减模型,研究成果为评估高速铁路隧道内火灾烟气纵向蔓延对人员疏散的影响提供了数据和理论支撑。[Objective]The design of Chinese high-speed railway tunnels,characterized by their high arched ceiling and large sections,presents unique challenges in terms of heat and mass transfer behaviors.These architectural features significantly influence the dynamics of smoke movement,resulting in distinctive patterns of longitudinal flow and temperature distribution of smoke during a fire,which differ markedly from those observed in conventional highway tunnels.[Methods] To investigate the specifics of smoke flow dynamics,this study embarked on full-scale fire experiments conducted within the Baijiashan tunnel of the Yuxiang high-speed railway between Chongqing and Qianjiang.These experiments were instrumental in capturing critical data on flame height and longitudinal distribution of smoke temperature under various fire scenarios.Building on this empirical foundation,the study analyzed the combustion stages and calculated the longitudinal smoke velocity for each fire scenario examined.[Results]Previous literature has highlighted that the heat release rates in full-scale experiments were calculated based on the equivalent diameter of fire sources,with values of 0.38,1.01,and 2.52 MW,respectively.It was observed that as the heat release rate increased,there was a corresponding significant uptick in the longitudinal velocity of the smoke.Within the confines of a high-speed railway tunnel,the vertical temperature distribution of fire smoke exhibits a distinct top-hat pattern.This characteristic distribution remains consistent farther from the fire source.Furthermore,this study delineates the boundary between one-dimensional shooting flow(Region II)and critical flow(Region II)within the context of a Chinese high-speed railway tunnel,identified as r/H~3.85 based on experimental data.The study also probes into the suitability of existing models for predicting the longitudinal flow and temperature distribution of fire smoke in long,narrow spaces such as high-speed railway tunnels.It was found that owing to the extended length

关 键 词：高速铁路隧道 全尺寸火灾实验 火灾烟气 纵向流动 纵向温度分布 

分 类 号：U458[建筑科学—桥梁与隧道工程]