三重介质不稳态窜流渗流模型与试井曲线分析

FLOW MODEL OF TRIPLE-MEDIUM WITH TRANSIENT INTERPOROSITY FLOW AND WELL-TEST CURVE

针对实际中存在介质之间发生不稳态窜流的情形,建立了考虑井筒储集和表皮效应在不同外边界条件下的三重介质不稳态窜流新模型,并对模型进行了求解,绘制了试井曲线。研究结果表明,与常规的三重介质拟稳态窜流模型相比,不稳态窜流模型所对应的压力导数曲线上的两个"凹子"明显变浅,且下凹不会低于0.25线;同时还分析了储容比以及窜流系数对曲线特征的影响。所获得的结果可用于研究介质之间发生不稳态窜流的三重介质储层中的流体渗流规律,进行压力动态和试井分析。

In terms of the transient interporosity flow between media,considering the wellbore storage and skin effects,the cor-responding new triple-medium model with transient interporosity(low has been established,which considers different outer bounda-ries conditions.The Laplace space analytic solution has been ob-tained and the well - test curve has been drawn up.The study re-sult shows that;compared with conventional triple medium model using the pseudo - steady interporosity flow approximation,the depth of the two 'hollow' on the derivative curve,corresponding transient interporosity flow model,becomes obviously shallow,with 0.25 as its minimum concave.At the same time,the effects of storativity ratio and interporosity flow coefficient on the sample curve characteristics were discussed.The results achieved can be used in the study of the flow rule,pressure behavior and the well test analysis of triple - porosity with transient interporosity flow in naturally fractured-vuggy carbonate reservoirs.