基于时空分布特征的煤层瓦斯测压准确性研究

为获得真实可靠的现场实测煤层瓦斯压力,实现煤层突出灾害等级科学评价和精准防治,通过理论分析、数值模拟和现场验证相结合的方法,以双重孔隙介质为基础,根据煤层瓦斯流动模型和瓦斯压力恢复曲线,分析煤层瓦斯压力测定的时空分布及准确性,并以桃园煤矿Ⅱ1采区10煤层为例,开展工程验证。研究结果表明:当基质瓦斯压力与裂隙瓦斯压力处于动态平衡时,所测得的煤层瓦斯压力最为准确;所构建的用于COMSOL解算的煤层测压瓦斯流动方程,可实现瓦斯压力时空分布的准确模拟;当煤层实测瓦斯压力恢复曲线与模拟分布特征一致且处于工程预测值范围内,可以判定结果为真实值;现场工程验证了实测瓦斯压力恢复曲线与模拟结果一致,测压结果准确。

Study on accuracy of coal seam gas pressure measurement based on its spatial and temporal distribution characteristics

In order to obtain reliable field measured results of coal seam gas pressure and realize scientific evaluation and precise prevention for coal seam outburst disasters,theoretical analysis,numerical simulation and field test were utilized to analyze spatial and temporal distribution of measure gas pressure based on gas flow model and gas pressure recovery curve with dual pore medium as object.Then engineering verification was carried out in No.10 coal seam in Taoyuan coalmineⅡ1 mining area.The results show that when matrix gas pressure and fracture gas pressure are in a dynamic balance,the measured results are the closest to real value.Accurate simulation of gas pressure spatial and temporal distribution could be realized by using gas flow equation of coal seam pressure measurement with COMSOL.When measured gas pressure recovery curve is consistent with simulated distribution regulation,and falls within engineering range of predictive values,it could be considered as real value.So the field measurement is accurate as it shows the recovery curve’s consistency with simulated results.