【摘要】 本文研究了有钻孔煤层瓦斯流动方程、数值解的近似表示,并用一维瓦斯流动实验和三个煤矿的大量考察验证了它的解,结论如下: 1.煤层中的瓦斯流动可以用建立在达西渗透定律基础上的瓦斯流动方程来描述。 2.平均隐式差分预估-校正法是解瓦斯流动方程的有效方法。 3.均质煤体的瓦斯压力、瓦斯流量规律近似符合实际煤层情况。 4.瓦斯压力分布、钻孔瓦斯比流量和总流量的近似式可以应用在以下情况: ①用无限流场单一钻孔总流量计算煤层平均透气性; ②用钻孔瓦斯比流量按曲线拟合随机尝试法计算煤层原始瓦斯压力; ③计算单一钻孔的无限流场和多钻孔的有限流场的瓦斯抽排放效果(瓦斯压力分布、钻孔瓦斯比流量和总流量); ④用流场某点所测的瓦斯压力计算等效透气性; ⑤计算抽排放钻孔间距和抽排放时间。更多还原

【Abstract】 This paper studies an equation of gas flow in a seam with boreholes and an approximate expression of numerical solution. The solution was checked by one dimensional gas flow experiments and field investigations in three mines. The conclusions are as the following.1. The gas flow in a coal seam can be described by gas flow equation of Darcy’s Law.2. The average implicit difference prediction and correction method is an effective method for solving gas flow equation.3. Laws of gas pressure and flow in homogenous coal mass are approximately similar to the actual seam conditions.4. The approximate expression for calculating distribution of gas pressure, the specific gas flow and total flow can be applied in the following conditions:(a) to calculate average gas permeability of a coal seam by using the total flow from a single borehole in an infinite flow field.(b) to compute the original gas pressure in a coal seam with specific gas flow in a borehole by use of a curve fitting random approach method.(c) to calculate results (distribution of gas pressure, the specific gas flow and total flow in a borehole) of draining gas from a single borehole in infinite flow field and from multiple boreholes in a finite flow field.(d) to compute equivalent gas permeability by measured gas pressure at a certain point in the flow field.(e) to compute time and borehole spacing for gas drainage.更多还原