基于移动坐标下“U”型与“U+I”型通风方式下采空区遗煤瓦斯涌出对比分析

Contrastive Analysis of Gas Emission of Residual Coal in Goaf Under U Shape and U+I Shape Ventilation Based on Moving Coordinate

利用CFD三维可视化数值模拟技术分别对"U"型与"U+I"型通风方式下采空区瓦斯运移进行了模拟计算,运用UDF接口建立了基于工作面移动坐标下的采空区遗煤瓦斯渗流计算模型与回采巷道内瓦斯弥散运移计算模型,定量对比研究了不同工作面推进速度和工作面配风量条件下2种通风方式下采空区瓦斯涌出的差异性,研究结果表明:"U"型通风方式下回风巷瓦斯浓度大小约为"U+I"型通风方式的2倍,随进风巷风速增大,"U+I"型通风方式和"U"型通风方式下回风巷瓦斯浓度均呈现减幅形式减小,随工作面推进速度增大,"U"型通风方式下回风巷瓦斯浓度呈减幅形式增大,而"U+I"型通风方式下回风巷瓦斯浓度呈现近似线性形式增大,相比于"U"型通风方式,"U+I"型通风方式下上隅角瓦斯浓度可降低25%~50%。

By CFD numerical simulation technology of 3D visualization,we simulate gas transport in goaf under U ＋ I type ventilation and U type ventilation. Though UDF interface,we establish gas seepage calculation model of residual coal in goaf and gas dispersion migration calculation model in mining roadways based on moving coordinate,and quantitatively analyze the difference of gas emission in gob of advancing speed and air distribution quantity of different working faces under two kinds of ventilation model. The results show that gas concentration in air return laneway under U shape ventilation system is two times than that under U ＋ I shape ventilation system; with the increase of working face advancing speed,gas concentration in air return laneway under U shape and U ＋ I shape ventilation systems decreases in damping form. With the increase of working face advancing speed,gas concentration under U shape ventilation system in air return laneway increases in damping form and gas concentration under U ＋ I shape ventilation system in air return laneway increases in approximate linear form. Gas concentration in the upper corner under U ＋ I shape ventilation system can reduce25% to 50%.