低渗透气藏垂直裂缝井椭圆渗流模型研究

针对低渗透气藏垂直裂缝井的渗流过程，考虑了非线性渗流和介质变形系数的影响，建立了椭圆渗流模型。根据此模型可以模拟气井生产压力降落过程中及关井压力恢复过程中地层压力分布状况。计算结果表明：在不稳定渗流早期，即压力波传播的第一阶段。压降漏斗曲线随时间不断扩大和加深；关井之后地层压力逐渐恢复，井底附近地层关井瞬间，地层压力上升趋势较为明显，关井时间越长，距离井底越远，地层压力上升速度越小。

Study on Elliptic Seepage Model For Wells Eith Vertical Fracture in Low Permeability Gas Reservoir

Elliptic seepage flow model was established to described seepage law in low permeable gas reservoirs of media deformation with vertical fracture well considering non-linear seepage and deformation coefficient, pressure distribution in reservoir and fracture can be simulated for gas well production, and pressure distribution in reservoir and fracture also can be simulated for shut-in pressure behavior based on this model. Computational results show that pressure cone of depression enlarge and deepen at the early stage of unstable flow, and that the pressure increase obviously in bottom-hole area during shut-in, and that the farther from bottom hole and the longer from shut-in, the the slower pressure increase.