A novel semi-analytical model for finite-conductivity multiple fractured horizontal wells in shale gas reservoirs

The use of multiple fractured horizontal wells (MFHWs) is considered an effective means for developing shale gas reservoirs, and a variety of models have recently been introduced to study the pressure behaviors of MFHWs in shale gas reservoirs. However, most of the existing models are based on some ideal assumptions that may not always be true in practice. This paper presents a novel semi-analytical model for finite-conductivity MFHWs in shale gas reservoirs with consideration of more actual conditions, such as finite-conductivity fractures, different fracture lengths, different fracture intervals, various angles between the fractures and the horizontal well, fracture asymmetry about the horizontal well, and partially penetrating fractures. Laplace transform, source function, numerical discrete method, and Gaussian elimination method are applied to solve the present model. The solution is presented in Laplace space so that the effects of the wellbore storage and skin can be easily incorporated by Duhamel's principle. Type curves of the pressure responses are plotted, possible flow regimes are identified, and a detailed analysis of the pressure characteristics is presented. The present model is much closer to the conditions of an actual reservoir, and thus it can be applied to an accurate interpretation of the pressure data of an MFHW in a shale gas reservoir. (C) 2015 Elsevier B.V. All rights reserved.