بررسی تاثیر شبکه شکاف گسسته بر رفتار فشارگذرای محیط متخلخل شکافدار

Abstract

The most famous theory for analyzing the pressure data of NFRs is the dual-porosity model presented by Warren and Root. Recent studies have shown that the dual-porosity model because of restricting assumptions may not be appropriate for interpreting well test from all NFRs. In this study, the pressure transient response of naturally fractured reservoirs was investigated using numerical simulation without considering analytical and semi-analytical methods. To this end, a set of models, including connected and disconnected fracture networks, was simulated in Eclipse software. The Warren and Root's well-testing signature was observed in all simulations but is was highly obvious for a well is located in the matrix and was negligible for a well is intersected by fractures. Because this phenomenon happens quickly for a well is intersected by fractures, and it's virtually impossible to record such an event in reality. The results of the simulation for a well is intersected by fractures showed a bilinear flow regime with a slope of 1/4. The period of this flow regime increased in the unconnected fracture network and changed to the linear flow regime with a slope of 1/2 in two cases 1: increasing fracture permeability in the connected fracture network 2- small-unconnected fractures. Moreover, the sensitivity analysis was performed on the well location in a connected fracture network. Results showed that by decreasing the well distance to the fracture network, the transition period becomes deeper and appears earlier.