An analytic solution for finite-conductivity, vertically fractured wells is developed for both the constant-pressure and the constant-rate cases1,2 . This solution includes linear skin on the fracture, wellbore and fracture storages, wellbore phase redistribution, and fracture-to-formation height ratio. The Laplace-space solution is direct, and no convolution is performed to include the skin, storage, and phase segregation effects.

This paper presents type curves and corresponding analysis techniques for constant-pressure declining rate cases. A unique asymptotic approach to pseudoradial flow is used to produce the solutions for the unbounded reservoirs. The type curves provide all possible flow regimes encountered in pressure transient testing of finite-conductivity, vertically fractured wells. Tabulated comparison between this analytic solution and the ones obtained with finite-difference simulator for both bounded and unbounded formations are also provided.

Keywords:
pressure transient analysis, fracture skin, linear fracture skin, pseudoradial flow, drillstem testing, conductivity, performance prediction, upstream oil & gas, type curve, pressure transient testing
Subjects:
Hydraulic Fracturing, Formation Evaluation & Management, Pressure transient analysis, Drillstem/well testing
Copyright 1991, Society of Petroleum Engineers
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