Numerical study of influence of hydraulic fracturing on fluid flow in natural fractures

Abstract

The hydraulic fracturing operation is highly complex in fractured reservoirs. The Fundamental key to a successful operation is processing and analysis of the propagation of hydraulic fracturing in a natural fracture network. In this paper, the hydraulic fracturing process is evaluated in a fractured reservoir in southwest Iran. The developing process of induced fracture in a natural fracture network is analysed by the Distinct Element Method (DEM). After determining the fluid flow regime in the natural fractures of the reservoir, hydraulic fracturing is applied along different lengths of the reservoir and in each range, the production rate is checked. Fluid flow in natural fractures after the hydraulic fracturing operation is shown and evaluated in order to evaluate the induced fracture effectiveness in enhancing fluid flow regimes in the reservoir. The reverse suction phenomenon which causes changes in the fluid flow pattern in fractures and will thus affect the production rate is also studied in this paper. Fracture coalescence will cause the induction of natural fractures to hydraulically fracture without their intersection; this is one of the significant parameters in hydraulic fracturing in naturally fractured reservoirs which is also discussed in detail. This paper can present valuable information on fluid flow analysis before and after applying hydraulic fracturing in a fractured reservoir and solve some essential ambiguities in this area.

Keywords

Hydraulic fracture / Fractured reservoirs / Production / Coalescence / Fluid flow

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