裂缝参数对考虑滑脱效应页岩气水平井产能的影响

Influence of fissure parameters on production capacity of shale gas horizontal wells considering slippage effect

低渗透页岩气藏中,气体渗流时会受滑脱效应的影响。建立了考虑滑脱效应的气、水两相页岩气藏渗流数学模型,并建立了理想地质模型,采用数值模拟方法,研究了水力压裂的不同裂缝参数对水平井产能的影响。模拟结果表明:裂缝条数、长度和间距是影响页岩气井产能的重要参数,而裂缝宽度和渗透率对产能的影响相对较弱;页岩气井的产能随着裂缝条数和裂缝长度的增加而增大;水平井的水平段长度及裂缝条数一定时,可通过增大裂缝间距来减少裂缝间的相互干扰。

In shale gas reservoir with low permeability, gas seepage is influenced by slippage effect. A mathemati-cal model of two-phase （gas-water） shale gas reservoir with consideration of slippage effect and an ideal geological model were established. Numerical simulation was performed for the different parameters of horizontal well frac-ture impact on production capacity after hydraulic fracturing. The simulation results show that the number, the length and the spacing of fractures are the important parameters for shale gas well production capacity. As the number and the length of fractures increase, the production capacity increases. When determining horizontal sec-tion length and the number of fractures, enlarging the space between fractures can reduce the mutual interference. The effect of fracture width and permeability on the production capacity is relatively insignificant.