【作者】 李杰林；

【导师】 周科平；

【作者基本信息】 中南大学 ， 安全技术及工程， 2007， 硕士

【摘要】 矿山火灾是矿井重大灾害之一,它对井下人员的生命安全、矿井设备、矿产资源以及地表环境都会造成很大的危害。在所有的矿井火灾中,自燃火灾约占70%以上。因此,研究矿井自燃火灾,对于矿山的安全生产以及社会的稳定有着重要的意义。研究矿井自燃火灾烟气流动特性是认识矿井自燃火灾规律、建立预测理论、开发防治技术的基础。本文以广西铜坑锡矿细脉带矿体发火区为研究对象,在分析总结了有关矿井自燃火灾烟气发生、发展过程规律的研究成果基础上,针对铜坑矿的矿石自燃发火场景,建立了矿井自燃火灾发展过程的数学模型和物理模型。首先把火源简化成一高温定温区,采用Airpak软件对自燃发火巷道烟气流动的规律进行了数值模拟计算,对不同火源区位置、不同火源区温度条件下场分布进行研究,得出了火灾后巷道中的速度场、温度场、污染物浓度场等分布,并且利用热舒适指标PMV—PPD对火灾后巷道、采场中的空气质量进行了安全评价;其次又在恒定火源情况下,采用Fluent流体软件对火灾烟气流动规律及温度场分布进行了瞬态模拟计算,分析了不同的风速条件对烟气流动变化及温度场分布的影响,得出了不同风速条件下巷道断面内的温度场分布随时间变化的结果。最后,针对矿井火灾后形成的井下高温热环境,进行了数值计算,并应用热舒适性的PMV评价指标,对不同设计参数的井下环境的热舒适程度进行了评价,确定了最优通风降温排烟方案。论文通过实验和数值模拟对矿井自燃火灾过程进行了研究,揭示了烟气在时空上的流动规律、温度和浓度变化规律,以及火灾的发生、发展过程;同时,对火灾后所造成的井下热环境问题,进行了安全评价。所得出的结论为判定实际条件下的矿井自燃发火区域及其动态发展变化的过程提供了理论基础;为铜坑矿地下火和毒气蔓延的控制以及火区特大事故应急救援预案的制定,保证细脉带矿体的安全回采提供了可靠依据;对于其他类似矿山的火灾防治,将灾后所造成的灾害减少至最低,也有着重大的意义。更多还原

【Abstract】 The fire is one of the magnitude disasters in the mine. It will take serious harm to humans, equipment, resource in the mine, and also effect the ground environment. Spontaneous fire has taken 70% in the total of mine fire. So, the research of mine spontaneous combustion has significant value for the mine safety and social stabilization.Research the rule of smoke flow in the mine fire is the basis of cognizing the law of mine spontaneous fire, building the theory of prediction, doing the technology of prevention and cure research. This paper takes the case of Tongkeng mine which located in Guangxi province for example, summarizes and analyzes the results of the law of fire smoke flow during the process of the fire. Based on the actual fire scene, the model of mathematic and physics about the process mine fire spread were built. Firstly, the fire source have been predigested, and fire smoke flow properties in fire tunnel were simulated and computed by using the Airpak software so as to obtain the distributing condition of velocity field, temperature field and contamination field in the fire tunnel, and the quality of the air in the fire tunnel and stope were evaluated by using the Predicted Mean Vote (PMV) and Predicted Percent Dissatisfied (PPD). Then, fire smoke flow properties and temperature field were simulated and computed by using the Fluent software under unsteady properties so as to obtain the distributing condition of temperature field in the vertical and transect of the fire tunnel under different velocity conditions. At last, based on the thermal environment with high temperature after fire in the mine, this paper made a numerical simulation, and the thermal comfort of environment with different design parameters in the mine were evaluated by predicted mean vote, and make out the best ventilation program.In this paper, experimental and numerical studies are carried out on mine spontaneous combustion process, and reveal the flow, temperature and concentration law of the smoke on space-time as well as the process of how the fire happen and develop. In addition, the thermal comforts of environment with high temperature after fire in the mine were evaluated by predicted mean vote. The results offer the theory basis to determinant the process of how the smoke spread and the dynamic development under actual condition, and provide a technical basis for controlling the fire and preventing the smoke spread, and making the scheme of accident urgent rescue. It also offered the reference value for the fire prevention and cure in the similar spontaneous combustion mine, and bring the lowest influence of the fire.更多还原