为了准确预测计算动态推采期间回采工作面煤壁瓦斯涌出量，以超化煤矿22051综采工作面为研究对象，建立煤层多组分瓦斯含量-压力赋存模型，考虑了工作面推进速度、采动影响下煤层渗透率变化，通过引入移动坐标系和采动作用下工作面前方煤层渗透率分布模型，构建了动态推采期间工作面煤壁多组分瓦斯涌出数值计算模型，采用有限差分法编制相应的解算程序，模拟计算回采工作面煤壁瓦斯涌出量。以瓦斯平衡方程、风量平衡方程为基础构建工作面瓦斯涌出量分源测算数学模型，结合工作面现场风量瓦斯分段测定法，实测了工作面煤壁瓦斯涌出量。对比分析了22051工作面煤壁瓦斯涌出量数值模拟结果与实测结果，研究表明：该工作面煤壁瓦斯涌出数值计算模型中工作面平均日推进速度参数应该由该工作面25～35 d的实际推进度计算得到，工作面回采进尺状况对工作面煤壁前方煤层瓦斯渗流运移具有重要影响作用，该工作面在当前开采条件和煤层瓦斯赋存渗流条件下，工作面煤壁瓦斯涌出量取决于25～35 d的工作面回采进尺状况，工作面煤壁瓦斯涌出存在明显的时间累加与延迟效应。

In order to accurately predict and calculate the gas emission from the coal wall of the working face during the dynamic mining period,No. 22051 fully-mechanized mining face of Chaohua Coal Mine was taken as the research object to establish the multi-component gas content pressure model of coal seam. Considering the advancing speed of the working face and the change of coal seam permeability under the influence of mining, and by introducing the moving coordinate system and the coal seam permeability distribution model in front of the working face under the action of mining, the simplified calculation model of gas emission from the coal wall during the dynamic pushover mining was established, and the corresponding calculation program was compiled by the finite difference method. Based on the gas balance equation and air volume balance equation, a mathematical model for the calculation of gas emission from the working face was established, combined with the on-site gas volume measurement method at the working face, and the gas emission from the coal wall of the working face was measured.The results of numerical simulation and actual measurement of gas emission from the coal wall of No.22051 working face were compared and analyzed. The results show that in the numerical model of gas emission from the coal wall of the working face, the parameter value of the average daily advancing speed of the coal face should be calculated from the actual advancing degree of the coal face within 25～35 days.The mining footage condition of the working face has an important effect on the gas seepage and migration in the coal seam in front of the coal wall of the working face. Under the current mining conditions and coal seam gas occurrence and seepage conditions, the amount of gas emission from the coal wall of the coal face depended on the mining footage within the time range of 25～35 days, and there were obvious time accumulation and delay effects in the gas emission from the coal wall of the coal face.

0 引言

1 回采工作面概况

2 工作面煤壁多组分瓦斯涌出数值计算模型构建

   2.1 工作面煤壁前方煤层多组分瓦斯渗流数学模型

   2.2 采动影响下工作面前方煤层渗透率分布模型

3 工作面煤壁多组分瓦斯涌出数值计算模型解算方法

   3.1 计算区域网格划分及边界条件设置

   3.2 输运控制方程离散化处理及解算程序

4 工作面煤壁瓦斯涌出量现场测试

   4.1 工作面瓦斯涌出量分源测试方法

   4.2 工作面煤壁瓦斯涌出量现场实测结果

5 工作面煤壁多组分瓦斯涌出数值计算模型现场应用

   5.1 工作面煤壁多组分瓦斯涌出数值计算模型模拟计算

   5.2 现场实测结果与计算模型模拟结果对比分析

6 结论