考虑滑脱效应的水气耦合煤层气渗流数值模拟

Coal-bed methane percolation numerical simulation considering gas slippage and water-gas coupling

建立了考虑滑脱效应影响的水、气两相流阶段的非线性渗流耦合模型,采用数值模拟手段研究了考虑水气耦合作用下的煤层气运移规律.得到了以下重要结论:在考虑水气耦合的煤层气渗流时,滑脱效应对压力场的影响不明显;气相相对渗透率对水相饱和度的影响很大,气相相对渗透率越大,相对研究区域水相饱和度变化的范围越大,变化越显著;时间效应对水相饱和度变化速率有很大的影响.

Established the non-linear seeping coupling model that considers the gas slippage and the situation that coal-bed methane dissolving in water. The law of coal-bed methane seeping was researched when both considered the gas slippage and water-gas coupling by finite element numerical simulation method. Some important conclusion can be gained： when considering water-gas two phase flow, the influence to the pressure field is not obvious by gas slippage; the gas relative permeability has significant influence to the water saturation; the time effect has significant influence to the changing rate of water saturation.