裂缝性储层压裂水平井压力动态分析

利用点源函数和叠加原理,建立并求解裂缝性储层压裂水平井数学模型,绘制并分析压力动态曲线。结果表明:裂缝性储层压裂水平井的流动形态可分为井筒储存、第一线性流、第一径向流、第二线性流、拟稳态窜流和第二径向流等6个主要阶段;裂缝半长一定下,裂缝间距越大,第一线性流持续时间越短,第一径向流持续时间越长;储能比决定窜流过渡段的凹槽宽度和凹陷深度;窜流系数决定窜流过渡段的凹槽位置。该研究成果可为裂缝性储层压裂水平井的动态分析及试井解释提供依据。

Pressure Transient Analysis of Fractured Horizontal Wells in Naturally Fractured Reservoirs

A fractured horizontal well mathematical model was established and solved by using function theory and superposition principle in naturally fractured reservoirs;the pressure transient curves were analyzed. The results show that there are six main flow regimes, including wellbore storage, first liner flow, first radial flow, second liner flow, inter-porosity flow, second radial flow; when fracture half-length is constant, the bigger the spacing between the fractures, the shorter the period of first liner flow and the longer the first radial flow; the storage ratio affects the groove width and depth in pressure derivative curves;the inter-porosity flow coefficient affects the groove location in pressure derivative curves. The study has guiding significance to the dynamic analysis and well test interpretation of fractured horizontal wells in naturally fractured reservoirs.