Novel approach to well test design and analysis for the wells with hydraulic fractures in waterflooded reservoirs is considered. General pitfalls and misuses of single well approach when applied to such systems are shown. It is revealed that for many practically important fractured wells cases conventional methods of infinite-acting radial flow regime identification are inapplicable. New technique of radial flow identification for such wells and capturing neighbor wells impact is introduced, practical examples are considered.
Approach proposed is based on the exact line-source solution in the form of integral exponent unlike the traditional method of interpretation which implies the logarithmic approximation. It is shown that for wells with highly conductive extensive fractures typical time of the beginning of logarithmic approximation can substantially exceed the actual time of the beginning of infinite-acting radial flow. In this case end of bilinear flow and beginning of radial flow can be estimated based on reservoir permeability assumptions or on comparison of the bottomhole pressure dynamics with exact line-source solution for a radial well with effective radius.