煤与瓦斯突出及煤-瓦斯两相流动力致灾多场耦合试验研究

With the field of coal mining continues to extend to the deep mining, coal and gas outbursts have become one of the major threats to the safe and efficient mining of coal. The project aims at the key scientific problems in coal and gas outburst and its risk analysis and control of dynamic disasters, to study the damage and mechanical behavior of gas-containing coal structure under multi-coupling effects of in-situ stress field, seepage field and temperature field and its influence on gas desorption kinetics. On the basis of the above, carry out physical simulation experiments of coal and gas outburst and its dynamic disasters under different test conditions of different earth stress, gas pressure and coal metamorphism. So as to reveal the law of dynamic evolution of coal physical parameters and coal-gas two-phase flow in the roadway during coal and gas outburst caused by the true three-dimensional dynamic and static loads, to clarify the mechanism of coal and gas outburst and the law of two-phase flow, to construct the main controlling factors system of dynamic disasters based on the actual coal mine engineering, to establish the prediction model of the coal and gas outburst and its dynamic disasters risk analysis model to form the theoretical system of dynamic disasters and risk control. Subsequently, providing theoretical support and engineering guidance for the prevention and control of coal and gas outburst in deep mines.

随着煤炭开采快速向深部转移，煤与瓦斯动力灾害已成为煤炭安全高效开采的主要威胁之一。本项目针对煤与瓦斯动力致灾机制及其控制理论中的关键科学问题，采用实验室试验、理论研究、数值模拟分析及工程实际相结合的研究方法，在阐明多场联动效应下含瓦斯煤结构损伤与力学行为及其对瓦斯解吸动力学特性影响的基础上，开展地应力、瓦斯压力、煤变质程度等不同试验条件下的煤与瓦斯突出及煤-瓦斯两相流动力致灾物理模拟试验研究，以揭示真三维动、静荷载作用下煤与瓦斯突出过程中煤体多物理场参量时空演化规律及煤-瓦斯两相流在巷道中的运移流动规律，明晰煤与瓦斯突出孕育灾变机理及其煤-瓦斯两相流动力致灾机制，提出基于煤矿工程实际的煤与瓦斯突出动力致灾主控因素体系，建立煤与瓦斯突出孕育灾变预测模型及其动力致灾风险分析模型，形成煤与瓦斯突出动力致灾及其风险控制理论体系，为控制煤与瓦斯突出提供理论支撑。

煤与瓦斯突出作为煤矿生产过程中的一种典型动力灾害，严重制约着目前“智慧煤矿”的安全、高效和绿色发展步伐，影响着煤矿领域关于我国“深地”和“深蓝”战略的实施。为进一步认识煤与瓦斯突出发生机理及其动力致灾机制，本项目在系统分析了多场联动效应下含瓦斯煤结构损伤与力学行为及其渗透特性的基础上，采用实验室试验、理论研究及数值模拟分析相结合的研究手段，开展了以下研究工作：1）基于突出关键体结构提出了“煤-瓦斯-围岩-巷道”突出系统的概念，并自主研制了一套可用于开展煤与瓦斯突出物理模拟试验研究的多场耦合煤矿动力灾害大型物理模拟试验系统；2）开展了不同煤层瓦斯压力、不同地应力及不同巷道组合方式条件下的煤与瓦斯突出物理模拟试验，分析了该过程中煤体不同区域内的地应力、瓦斯压力和温度等热-流-固体系状态参数的时空演化规律，以及巷道中煤-瓦斯两相流的冲击力、温度、静压等多物理参数时空演化规律及突出煤的分选和沉积特征；3）结合热力学、空气动力学、流体力学等理论提出了包含三个关键结构的煤-瓦斯流动可变收放物理模型(PCEF模型)，揭示了突出煤-瓦斯两相流动模式以及在该过程中巷道内的复杂波系形成机制；4）构建了煤与瓦斯突出过程中含瓦斯煤体瓦斯内能、受载煤体弹性潜能、突出煤体所受抛出功、突出煤体所受破碎功等能量参数之间的量化转换关系；5）实现了基于OpenFOAM和PFC3D的FVM-DEM耦合数值算法，得到了突出过程中煤体颗粒的速度、煤体裂纹扩展、应力分布特征及突出强度的实时演化，以及煤-瓦斯两相流动过程中巷道内的静压分布、两相流速演化以及固相体积分数的分布特征; 6）基于贝叶斯网络初步构建了煤与瓦斯突出动力致灾主控因素体系。