钻孔瓦斯抽采流-固耦合数值模拟

Numerical Simulation of Gas Drainage from Borehole Based on Fluidsolid Coupling

为了探究钻孔瓦斯抽采过程中瓦斯压力随时间的变化规律,通过建立流-固耦合模型,考虑渗透率、孔隙率和体积应变的动态变化,结合矿井煤层物性参数,运用多物理场软件进行了模拟分析。分析结果表明:随着抽采时间的延长,钻孔周围煤体瓦斯压力逐步降低,在瓦斯抽采过程中,瓦斯压力的降低有助于渗透率的提高,但影响效果甚微,埋藏深度对煤层渗透率起主导作用。

In order to analyze the variation of the gas pressure with different time in the process of the gas extraction,the fluid-solid coupling model was established. The multi-physic coupling software was adopted in the consideration of the dynamic changing of the permeability,porosity and volume strain and the physical parameter of the coal seam.The results show that around the boreholes the gas pressure is rapidly decreased over time. In addition, the permeability of the coal seam is enhanced with the gas pressure decreasing and reduced with the burial depth of the coal seam increasing.