考虑流固耦合的立井揭煤瓦斯抽采模拟研究

Methane Drainage Simulation for Shaft Coal Uncovering Based on Solid-fluid Coupling Theory

瓦斯抽采对于立井揭煤具有重要的作用,传统的瓦斯抽采设计常依据经验或仅靠瓦斯在煤层中流动服从达西定律和质量守恒定律来判断和设计瓦斯抽采工程,没有考虑瓦斯的吸附作用和应力对煤层瓦斯流动的影响。在考虑流固耦合和瓦斯吸附作用的基础上建立了瓦斯流动方程,同时对不同煤层围岩应力下瓦斯流动情况作了分析,指出了围岩应力大小对瓦斯抽采具有重要的影响,围岩压力增大会导致瓦斯难抽出,残余瓦斯压力大;围岩压力越大,煤层渗透率越低。

Methane drainage plays on an important role in shaft uncovering coal. Traditional methane drainage design often relied on experience or only considered Darcy Law and mass conservation Law, but methane adsorption action and stress＇ s influence on meth- ane flow was not be considered. Methane flow equation considering solid-fluid coupling and adsorption action was set up; methane flow state under different stresses was analyzed. It was indicated that stress＇ s influence on methane drainage was large. Stress increasing would make methane drainage difficult, residual methane pressure was large. Stress was larger, coalseam permeability was lower.