SF_6示踪法结合数值模拟确定钻孔抽采有效半径的研究

Research on Determination of Effective Gas Drainage Radius of Boreholes by SF_6 Tracer Method and Numerical Simulation

为了准确测定煤层钻孔抽采有效半径,达到理想的瓦斯抽采效果,根据城郊煤矿深部煤层实际赋存条件,在对比分析多种测定钻孔抽采有效半径方法的基础上,将SF_6气体示踪法与COMSOL Multiphysics数值模拟法相结合,利用实测结果与模拟结果确定了该矿试验区钻孔抽采有效半径。研究结果表明:在抽采钻孔直径为92 mm、抽采负压为15 k Pa的条件下,预抽60 d后,钻孔抽采有效半径为1.73 m。

In order to accurately determine the effective gas drainage radius of boreholes in a coal seam and achieve an ideal gas drainage effect,the effective gas drainage radius of boreholes in the test area in Chengjiao Mine was determined according to the actual occurrence conditions of deep coal seams in this mine,based on the comparative analysis of various determination methods for the effective gas drainage radius of boreholes,with the combination of SF6 gas tracer method and COMSOL Multiphysics numerical simulation and by using the measured results and simulated results. The research results showed that when the diameter of gas drainage hole was 92 mm and the negative pressure for the gas drainage was 15 k Pa,the effective gas drainage radius was 1. 73 m after gas pre-drainage for 60 days.