Using Distributed Volumetric Sources to Predict Production from Multiple-Fractured Horizontal Wells Under Non-Darcy-Flow Conditions

Abstract

Summary The method of distributed volumetric sources (DVS) has been applied to predict gas production from a horizontal well with multiple transverse fractures in a bounded reservoir. Combining the quasianalytical DVS method, which provides us with the opportunity to predict pressure and production behavior of complex well/fracture configurations, with non-Darcy flow in the fracture enables us to calculate the optimum configuration in terms of the number and dimensions of fractures per well for a certain amount of proppant of a given type. The method is applied to an example case of a tight gas reservoir to maximize the production performance of this complex well/fracture configuration. Comparing results with and without inclusion of the non-Darcy effect in the fracture shows that a decrease in production occurs because of non-Darcy flow in all cases. However, a systematic screening of a realistic set of well/fracture configurations reveals that the detrimental effect of non-Darcy flow can be substantially compensated for by selecting the right number of fractures and shifting the fracture dimensions in favor of thicker fractures. While a simultaneous decrease in optimum lateral (and vertical) extension is necessary, it has limited effect on productivity. The simplicity, robustness, and small computational demand of the model allow seamless integration with external economic and operational constraints, providing a tool to screen and optimize a large set of possible configurations most suited for the development of economically marginal fields.