The Role of Geomechanical Properties in the Process of Hydraulic Fracturing Propagation by using Fictitious Discrete Fracture Network Technique

Document Type : Research Paper

Authors

Rock Mechanics Engineering Group, Technical and Engineering Department, Tarbiat Modares University, Tehran, Iran

Abstract

Hydraulic fracturing is one of the conventional and common methods to stimulate oil and gas formations with low permeability. This method is widely used for creating artificial fractures and stimulate fluid flow in oil and gas wells. In this paper, fracture propagation process was simulated by using a Discrete Fracture Network (DFN) in UDEC software. Discrete Element Method (DEM) is a key for simulating hydraulic fracturing which is capable of performing a fully coupled hydromechanical analysis to model fluid flow through a network of fractures. In this regard, fictitious joints were used for modeling fracture propagation in a medium with equal to intact rock properties. To achieve this goal, the mechanical and strength properties of discontinuities were considered equal to mechanical and strength properties of intact rock. Then, the role of rock mechanics parameters including elastic modulus, cohesion and friction angle were studied in the process of fracture propagation. The results of numerical simulations showed that the extended fracture length is increased by increasing the elastic modulus and decreasing the friction angle. Also, increasing in the cohesion does not have a significant effect on the extended fracture length, but it reduces the hydraulic fracture opening.
 

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