摘要
钻孔周围煤体中的瓦斯流动是一个复杂的非线性物理过程。应用Darcy定律、质量守恒定律建立了钻孔周围煤体中瓦斯不稳定径向流动的数学模型,利用FLAC3D中的有限差分方法对钻孔过程中孔壁瓦斯涌出进行模拟,得到此过程中瓦斯涌出速度、涌出总量与钻孔时间的关系,指出瓦斯涌出总量随着钻孔时间的增加呈3次多项式变化,而流速则呈倒抛物线形分布。研究结果表明,数值模拟能反映煤层瓦斯流动的基本规律,可为实际生产提供参考。
The gas flow in coal body around boreholes is a complicated nonlinear physical process. A mathematical model of unstable radial gas flow in coal body around boreholes was established by Darcy law and the law of mass conservation in this paper. The gas emission from hole wall in the drilling process was simulated by finite difference method in FLAC3D, and the relations between drilling time and gas emission rate, total amount of gas emission were obtained, which indicated that total amount of gas emission changed by third-degree polynomial function with the increase of drilling time, the gas emission rate changed by parabolic-index function. Study results showed that the numerical simulation can reflect the basic rules of gas flow in coal body around borehole, which thus provided a reference for actual production.
出处
《矿业安全与环保》
北大核心
2008年第6期4-6,共3页
Mining Safety & Environmental Protection
基金
国家973计划项目(2005CB221502)
