煤矿井下仰斜群孔疏水数值模型构建与涌水分析

Numerical model construction and analysis of water inflow from drainage of the inclined group holes in underground coalmine

为构建煤矿井下仰斜群孔疏水数值模型,提出了疏水含水层与仰斜疏水钻孔的水文地质模型的概化方法,建立达西非稳定流数学模型和定解条件以刻画仰斜疏水钻孔涌水时变衰减过程,采用COMSOL有限元三角四面体单元剖分方法构建出含水层与钻孔复合刻画的仰斜群孔涌水数值模型。并模拟分析了彬长矿区某采煤工作面在不同仰斜钻孔数和钻场间距条件下群孔涌水规律,模拟结果显示,随着钻孔数目和钻孔覆盖范围的增加,疏降水头高度影响范围增加明显,钻场和单孔稳定涌水能力减少明显,涌水量衰减速度相对增大,其似稳定周期变化不明显;随着钻场间距的增加,疏降水头高度影响范围增加明显,钻场和单孔的稳定涌水能力增大,涌水量衰减速度相对减小,似稳定周期似稳定周期变化不明显。论文研究成果为顶板水害科学钻探疏放治理实践具有指导意义。

In order to construct numerical model of drainage of the inclined group holes in underground coalmine,the generalization method of hydrogeological model of drainage aquifer and inclined drainage borehole was proposed,and the mathematical model of Darcy unsteady flow and definite solution conditions were established to describe decay process of water inflow from inclined drainage boreholes.In this paper,a numerical model of water inflow from inclined group holes with aquifer and borehole composite was established with COMSOL finite element triangulation tetrahedral unit method.The water inrush regularity of mining workface in Binchang coal mine was simulated and analyzed under different inclined borehole number and drilling field spacing.The simulation results have showen that with the increase of the number of boreholes and the coverage of boreholes,the influence range of water head height of drainage increases obviously,the stable water inflow capacity of drilling field and single hole decreases obviously,the water inflow decay rate increases relatively,and its quasi stable periodic change is not obvious.With the increase of drilling field spacing,the influence range of water head height of drainage increases obviously,the stable water inflow capacity of drilling field and single hole increases,the water inflow decay rate decreases relatively,and the change of quasi stable period is not obvious.The research results of this paper have guiding significance for scientific drilling and control practice of roof water hazard.