【作者】 张源；

【导师】 万志军；

【作者基本信息】 中国矿业大学 ， 采矿工程， 2013， 博士

【摘要】 热害已经成为继顶板、瓦斯、水、火、粉尘后的第六大矿井自然灾害。对于深部矿井，高地温因素在矿井热害的形成过程中起着决定性的作用，其中，高地温巷道以其通风线路长、暴露面积大、通风系统复杂等原因，最有可能在较大区域范围内影响到井下的气象环境。它不仅直接向风流传热使风温上升，还会对空调降温产生的冷空气造成热污染，降低人工制冷降温的效果。因此，需要研究高地温巷道围岩的传热问题，而其基本问题之一是巷道围岩的温度场。论文采用理论分析、物理模拟和数值试验相结合的方法，提出了适用于巷道围岩温度场研究的物理相似试验方法；利用自主设计研制的高地温巷道热湿环境相似模拟试验系统，开展了巷道围岩温度场的物理试验研究，揭示了高地温巷道围岩温度分布特征及其演化规律；建立了巷道围岩非稳态温度场的数值解法，进行了高地温巷道围岩温度场的数值试验，进一步探讨了巷道围岩温度时空分布的演化规律；建立了具有阻热圈结构的高地温巷道围岩非稳态导热的数学模型，首次给出了阻热圈温度场的数值解法，开展了阻热圈结构隔热机理的研究，进一步完善了阻热圈概念的内涵。主要研究结论如下：1)提出了适用于高地温巷道围岩温度场研究的物理相似试验方法。基于能量守恒定律和傅里叶定律，把高地温巷道围岩传热简化成一维半无限大单一介质空心圆薄片的导热问题，建立了巷道围岩非稳态导热的数学模型；依据相似理论，推导出了巷道围岩温度场的相似准则，得到了巷道围岩温度场物理模拟试验的相似常数关系式，在此基础上，提出了适合于高地温巷道围岩温度场研究的物理模拟试验方法。2)自主设计研制了高地温巷道热湿环境相似模拟试验系统。基于巷道围岩温度场相似准则及物理相似试验方法，自主设计研制了用于高地温巷道围岩温度场研究的试验系统。该系统能够进行井巷常规通风降温、空调降温、隔热降温等物理模拟试验，是目前国内外已知尺寸最大、功能最全的用于矿井高地温井巷热湿环境相似模拟的专用试验平台。3)开展了巷道围岩温度场的物理试验研究，揭示了高地温巷道围岩温度分布特征及其演化规律。采用自主设计研制的高地温巷道热湿环境相似模拟试验系统，研究了高地温巷道围岩温度分布特征及其动态变化规律，主要成果：（1）巷道通风以后，壁面温度急剧降低，很快就接近风温；随着通风时间的延长，温度扰动范围由浅到深逐渐扩展到巷道围岩深部；（2）巷道通风后，从巷道壁面到围岩深处，温度按指数函数（Θ=1-f₁（F_o, O） exp（f₂（F_o, O） R））形式逐渐增大；（3）随着通风时间的延长，巷道围岩温度以希尔方程（Θ=A/（F_o^m+B）+C）形式逐渐降低，在初期降低的幅度较大，整个过程中降幅在逐渐减小；（4）巷道围岩的温度梯度、热流密度和热流量的变化过程大致可以分成三个阶段，在围岩温度未被扰动时，温度梯度、热流密度和热流量均维持在很低水平；在围岩刚进入温度扰动范围到被充分扰动阶段，温度梯度、热流密度和热流量逐渐增加，直至到达峰值；围岩温度被充分扰动以后，温度梯度、热流密度和热流量逐渐降低，逐渐重新恢复到较低水平。4)进行了高地温巷道围岩温度场的数值试验研究，验证了物理相似试验结果及所建立的巷道围岩温度场数学模型的合理性，进一步探讨了巷道围岩温度时空分布的演化规律，主要成果：（1）利用数值方法，验证了物理试验中巷道围岩无量纲温度与无量纲半径之间符合指数函数、与无量纲时间之间符合希尔方程，以及温度梯度、热流密度和热流量具有三阶段分布特征等结论；（2）巷道围岩温度扰动范围与无因次时间之间呈幂函数关系（R=2.75Fo+1），对于与模拟条件接近的巷道围岩，其通风4年后进入准稳态，最大温度扰动范围25m左右；（3）巷道围岩无量纲温度与毕渥数Bi之间呈指数函数（Θ=A exp（BBi）+C）关系，Bi越大，无量纲温度越低，说明增大风速有助于加大排热量；当Bi达到极值以后，巷道围岩的温度并不随着Bi的增大而显著降低，说明风速增大到一定值后，降温效果不再明显。5)研究了具阻热圈结构巷道围岩温度分布特征及阻热圈隔热机理。建立了具有阻热圈结构的巷道围岩导热数学模型；采用热平衡法，建立了高地温巷道围岩阻热圈温度场的数值解法，编写了阻热圈温度场数值试验的专用计算机源程序，开展了阻热圈隔热结构隔热机理的研究，主要成果：（1）阻热圈内温度分布具有明显的分区域特点，区域界线处在喷浆层与注浆层，以及注浆层与深部岩体的交界面。（2）与无阻热圈的巷道围岩相比，有阻热圈结构的巷道围岩的温度场具有壁面温度低、内部温度高的总体特点；壁面温度在通风初期降低的速率更快，且喷浆层导热系数越小，壁面温度越低；（3）阻热圈内喷浆层和注浆层的导热系数越小，岩体内的温度就越高；（4）注浆层内温度分布分为两部分：靠近喷浆层的一小段区域是注浆层导热越好，其温度越高；靠近深部岩体的其余大部分注浆层区域是导热越好，其温度越低。（5）在阻热圈的喷浆层和注浆层内，其导热系数越小，温度梯度就越大，热流密度就越小，隔热效果越明显；在通风初期，相同的导热系数降幅，喷浆层隔热效果优于注浆层；通风3个月以后，注浆层的隔热效果优于喷浆层。（6）阻热圈结构对于减少巷道围岩散热效果显著，巷道服务期内可减排29⁴0%，且通风早期，效果更明显。更多还原

【Abstract】 Heat hazard has become the sixth largest natural hazard in underground mine,following after roof accident, gas disaster, water accident, fire disaster and coal dust.The geothermal temperature factor plays the decisive role in the formation of hightemperature damage in deep coal mines. Because of long ventilation lines, largeexposure area, and complex ventilation system, the high geothermal temperatureroadway most possibly influences the meteorological environment with largest regionin underground mines. It not only directly heats wind flow, but also indirectly reducesthe air-conditioning cooling effect by polluting cool air flow. Therefore, it is necessaryto research the heat transfer problems in surrounding rock of the high geothermaltemperature roadway, whose fundamental problem is the temperature field.This paper adopted the combined method of theoretical anlysis, physicalsimulation and numerical test to research the temperature field of surrouding rock ofroadway and its evolution law, and obtained some corresponding results. Similarsimulation test method for the research on the temperature of surrounding rock in highgeothermal roadway was proposed. With the similar simulation test system of thermaland humid environment in high geothermal roadway, designed and developedindependently, the paper carried on the research on temperature field, and revealed thetemperature distribution characteristics and their evolution laws in high geothermalroadway’s surrounding rock. A numerical solution method suitable for transienttemperature field was established to carry on the numerical test research ontemperature field of surrounding rock in high geothermal roadway, and the evolutionlaws of temperature field were further discussed. A mathematical model of transientconduction in surrounding rock with heat insulation zone in high geothermal roadwaywas established to carry on the research on insulation mechanism of the heatinsulation zone, and the scientific connotation of the heat insulation zone concept wasfurther perfected. The specific results are listed as follows:1) A physical similar simulation method suitable for the research on thetemperature field of surrounding rock in high geothermal roadway was proposed inthis paper. Based on the law of conservation of energy and the Fourier’s law, the heattransfer problem in surrounding rock of roadway was simplied to the heat conductionproblem in a semi infinite hollow circle slice with one dimension, and a mathematicalmodel for transient conduction in roadway’s surrounding rock was built. At the same time, this article derived the similarity criterion of temperature field in roadway’ssurrounding rock according to the theory of similarity, and got the relationalexpression of similarity constant in the process of physical simulation experiments oftemperature field of roadway’s surrounding rock. Finally, the paper anlyzed andsummarized the physical simulation method suitable for the research of thetemperature field of surrounding rock in high geothermal roadway.2) We designed and developed the Similarity Simulation Test System forThermal and Humid Environment in High Geothermal Roadway independently, withwhich the ventilation cooling, the air conditioning cooling and the insulation coolingcould be simulated. So far, the testing system is a specialized testing platform with thelargest size and the most perfect function at home and abroad, applied to simulate thethermal and humid environment in high geothermal roadway.3) Temperature distribution of surrounding rock in high geothermal roadway andits evolution law were investigated using the physical similarity experiment method.The main achievements are as follows:(1) After ventilation in roadway, the roadwaysurface temperature decreases rapidly, which would be soon close to the windtemperature; the temperature disturbance range of the surrounding rock expandsgradually from the shallow to deep.(2) The temperature of the surrounding rock inroadway grows exponentially from the surface to depth.(3) With the extension ofventilation time, the temperature of surrounding rock decreases as Hill function, andthe decreasing amplitude is also gradually decreasing.(4) The variation process oftemperature gradient, heat flux density and heat flux in roadway’s surrounding rockcould be divided into three stages. They keep a relatively lower level before thetemperature of surrounding rock is disturbed. When the surrounding rock enters theregion of temperature disturbance, the temperature gradient, heat flux density and heatflux will gradually increase until they reach the peaks. The third stage is when thetemperature of surrounding rock is fully disturbed. At that time, the temperaturegradient, heat flux density and heat flux gradually decrease, and finally return to avery low level.4) Transient conduction characteristics of surrounding rock in high geothermalroadway were studied with the numerical simulation method. The experimental resultsand the mathematical model of transient conduction of surrounding rock were provedreasonable, and the evolution laws of temperature field were further discussed. Themain achivements are as follows:(1) It is proved that the relationship between dimensionless temperature and dimensionless radio fits exponential function, and therelationship between dimensionless temperature and dimensionless time fits hillfunction by the numerical method. Meanwhile, it is proved that there are three stagesin the distribution characteristics of temperature grandient, heat flux density and heatflux.(2) The temperature disturbance range in surrounding rock is expanding toaround in a power function law as the transient conduction goes on. After ventilationfor4years, the temperature of the surrounding rock reaches quasi-steady state, andthe largest temperature disturbance range is about25meters.(3) The relationshipbetween dimensionless temperature and Bi fits exponential function, and the more theBi is, the lower the dimensionless temperature is, which demonstrates that increasingwind speed promotes thermal discharge. When the Bi reaches to the peak, thetemperature of the surrounding rock doesn’t decrease obviously with the Bi increasing,which demonstrates the cooling effect will not be obvious when the wind speedreaches to a certain high level.5) The temperature distribution characteristics and insulation mechanism of theheat insulation zone wer studied in the paper. Mathematical model for heat conductionin surrounding rock of high geothermal roadway with heat insulation zone was built inthis article. Based on the heat conduction characteristics of composite material, thenumerical solution method was also built by the energy balance method. Meanwhile,the special computer programme for temperature field simulation of heat insulationzone was written, with which the insulation mechanism of heat insulation zone wassimulated. The main achivements are as follows:(1) There exists obvious regionaltemperature distribution characteristic in the heat insulation zone, and the boundarylines are the interface between the spouting layer and the grouting layer, and theinterface between grounting layer and the rock mass.(2) The temperature of theroadway surface with heat insulation zone decreases more quickly during initialperiod of ventilation, and the lower the conductivity coefficient of the spouting layer,the temperature of the surface is lower.(3) The lower the heat conductivity coefficientof the spouting layer and the grouting layer, the higher the temperature of the rockmass in deep is.(4) The temperature distribution in the grouting layer can be dividedinto two parts. In the first part, whih is a small region close to the spouting layer, thebetter the heat conductivity of grouting layer is, the higher the temperature. In otherregion, the better the heat conductivity is, the lower the temperature is.(5) The lowerthe heat conductivity coefficient of the spouting layer and the grouting layer is, the larger the temperature grandient is, and the lower the heat flux density is, whichdemonstrates that the insulation effect is more obvious. During the preliminary stageof ventilation, the insulation effect of spouting layer is better than that of groutinglayer with the same decreasing amplitude of heat conductivity. However, theinsulation effect of grouting layer is better than spouting layer after3month’sventilation.(6) Researches show that the heat insulation zone is significantly effectiveto reduce heat dissipation of the roadway’s surrounding rock. There would be an about29~40%cut in heat emission, and the cooling effect is more obvious during thepreliminary stage.更多还原