【摘要】 为深入分析瓦斯在煤层内流动的阻力特性,根据煤层瓦斯径向不稳定流动理论,探讨煤层透气性系数的本质内涵及物理意义,指出其现场应用过程中存在的不足。基于无因次流量准数Y和时间准数F0之间的关系,对系数a,b值进行修正,提出透气性系数公式的优化计算方法。给出对比2种计算方法的现场应用实例。结果表明,优化方法的计算过程不必采用试算,计算结果的相对误差小于2%,可满足现场应用的实际要求。依据现场测定值可计算出AB的区间范围,据此可直接选择相应公式计算煤层透气性系数。更多还原

【Abstract】 The resistance characteristics of gas flowing in coal bed were analyzed thoroughly according to the theory of gas radial unstable flow,the hypostasis meanings and calculation method were discussed,and the deficiency was pointed out in locale application.Basing on the connection of dimensionless flow criterion Y and time criterion F0,coefficient a and b were modified and a straightforward calculation method of gas permeability coefficient was put forward.The new method was applied to locale and contrasted with original method,the results show that the optimized method does not need trial calculation and the result comparative error is less than 2%,which meet the practical requirements for field application.According to field measured values,interval of AB can be figured out,so corresponding calculability formula of gas permeability coefficient can be acquired straightly.更多还原