【作者】 李士戎；

【导师】 邓军；

【作者基本信息】 西安科技大学 ， 安全技术及工程， 2013， 博士

【摘要】 隧道空间狭长、密闭，火灾时高温与烟气会严重威胁内部人员生命及隧道结构安全，而着火机动车穿行隧道会使火灾过程更加复杂。论文针对着火车辆穿行隧道引发空间温度场及烟气蔓延动态变化的问题，通过移动火源隧道火灾相似模拟实验与数值模拟，研究移动火源对隧道空间能量分布以及烟气蔓延影响作用。研究结果对隧道火灾防治与救援相关研究与应用具有重要的实际指导意义。以发生过着火车辆穿行事故的法国勃朗峰隧道以及国内典型隧道结构为原型，自行设计搭建了1:20小尺寸隧道火灾特性相似模拟实验系统。通过燃料质量损失率实验，分析了火源移动对火焰湍动及稳定性的影响，建立了火焰形态改变、火源热释放速率与火源速度的对应关系函数。利用相似模拟实验系统，通过不同通风速率与火源条件下的相似模拟，研究了不同实验条件下空间内各位置温度曲线、时均温度以及温度极值等特征参数，结合火区热阻节流效应与活塞风效应分析。掌握了不同速度移动火源对隧道空间温度场分布及能量变化的影响规律，揭示了纵向通风与移动火源在隧道空间内相互制约与促进的作用关系。根据隧道火灾烟气蔓延相似模拟实验，研究了自然通风条件下，不同速度移动火源对隧道空间内烟气蔓延速度的影响作用。结合移动火源造成隧道空间活塞风及热阻作用综合效应分析，阐明了不同行进速度的移动火源对隧道空间内火源前、后不同区段内火灾烟气扩散与蔓延的非对称影响作用规律。基于数值传热基本原理，以相似模拟实验为原型，建立了隧道空间移动火源数值模型。通过火灾动力学数值模拟，分析了移动火源条件下隧道空间流场与压力变化、温度等值面与烟气浓度分布情况。得出了移动火源对隧道内气流场、压力场分布的影响规律，分析了纵向通风对热烟气回流的抑制作用，阐明了移动火源对被困人员的危害影响，并对着火车辆进入隧道初期的人员逃生与车辆引导提出指导性建议。更多还原

【Abstract】 Tunnel space is long, narrow and nearly airtight. Once fire occurs inside, heat flux ofhigh temperature and smoke will greatly threaten tunnel structure and lives of people involved,and moving vehicle on fire complicates the fire process. Targeting at dynamic changes oftemperature field distribution and smoke spread caused by moving vehicle on fire, the presentstudy uses analogy simulation experiment and numerical simulation to investigate theinfluence of moving fire on energy distribution and smoke spread in tunnel, which providesguidance for research and application on tunnel fire prevention and rescue.Taking the structure of Mont Blanc tunnel in which fire accident ever occurred due tomoving vehicle on fire and typical domestic tunnels as prototype, the1:20reduced-scaleanalogy simulation tunnel model system is designed and established based on research objects.Through mass loss rate test of fuel, turbulence and stability influenced by moving fire onflame are analyzed. The function of the relation between flame shape, heat release rate of fireand velocity of moving fire is obtained.Based on analogy experimental system, analogy simulation experiments are carried outon moving fire traveling in tunnel at different velocities. From the curve change oftemperature, time-averaged temperature and maximum temperature of different detectors intunnel is studied, combining with fire zone thermal resisting, throttling effect and thermalpiston wind effect analysis, the law of influence of moving fire with different velocities onspacial temperature field distribution and energy change is possessed. The mutual functionrelationship between longitudinal ventilation and moving fire in tunnel is revealed as well.Through analogy simulation experiment, the influence of moving fire with differentvelocities on smoke spread speed in tunnel under natural ventilation is studied. Combinedwith analysis of fire zone thermal resisting and throttling effect and thermal piston wind effect of moving fire synthetically functions on tunnel space, the law was drawn on relation ofmoving fire with different velocities asymmetrically influences smoke spread in forward andbackward parts of fire source in tunnel.Based on basic principle of numerical heat transfer and analogy simulation experiment,numerical model of moving fire in tunnel is established; through fire dynamic numericalsimulation, air flow filed, pressure field, temperature isosurface and smoke concentrationdistribution in tunnel under moving fire condition are studied;the law on influence of movingfire on air field and pressure field distributon in tunnel is drawn, and the restrain effect oflongitudinal ventilation on backflow of heat flux is analyzed. On the basis of the research,the threat of the moving fire to people trapped in tunnel is clarified, and the principle andmeasures are provided for people to escape and vehicles to be guided in the early age whenmoving vehicle on fire advances into tunnel.更多还原