Simulation of proppant transport at intersection of hydraulic fracture and natural fracture of wellbores using CFD-DEM--颗粒学报PARTICUOLOGY

Akhshik, S., & Rajabi, M. (2022). Simulation of proppant transport at intersection of hydraulic fracture and natural fracture of wellbores using CFD-DEM. Particuology, 63, 112-124. https://doi.org/10.1016/j.partic.2021.05.005

Simulation of proppant transport at intersection of hydraulic fracture and natural fracture of wellbores using CFD-DEM

Siamak Akhshik ^a *, Majid Rajabi ^b

a Department of Mechanical Engineering, Sharif University of Technology, Iran
b Sustainable Manufacturing Research Laboratory, School of Mechanical Engineering, Iran University of Science and Technology, Iran

10.1016/j.partic.2021.05.005

Volume 63, April 2022, Pages 112-124

Received 29 July 2020, Revised 14 May 2021, Accepted 21 May 2021, Available online 6 June 2021, Version of Record 18 November 2021.

E-mail: Akhshik@ioec.com

Highlights

• Proppants-fluid flow in hydraulic and natural fracture intersection is simulated by CFD-DEM method.

• Sphericity effects are analyzed for different fluid inlet velocities and HF-NF intersection types.

• A new definition called blockage coefficient is introduced indicating severity and partiality of blockage.

• Effect of proppants concentration is negligible when proppants motion mechanism is bed load transport.

Abstract

Proppants transport is an advanced technique to improve the hydraulic fracture phenomenon, in order to promote the versatility of gas/oil reservoirs. A numerical simulation of proppants transport at both hydraulic fracture (HF) and natural fracture (NF) intersection is performed to provide a better understanding of key factors which cause, or contribute to proppants transport in HF–NF intersection. Computational fluid dynamics (CFD) in association with discrete element method (DEM) is used to model the complex interactions between proppant particles, host fluid medium and fractured walls. The effect of non-spherical geometry of particles is considered in this model, using the multi-sphere method. All interaction forces between fluid flow and particles are considered in the computational model. Moreover, the interactions of particle–particle and particle–wall are taken into account via Hertz–Mindlin model. The results of the CFD-DEM simulations are compared to the experimental data. It is found that the CFD-DEM simulation is capable of predicting proppant transport and deposition quality at intersections which are in agreement with experimental data. The results indicate that the HF–NF intersection type, fluid velocity and NF aperture affect the quality of blockage occurrence, presenting a new index, called the blockage coefficient which indicates the severity of the blockage.

Graphical abstract

Keywords

Hydraulic fracture process; Proppants transport; CFD-DEM method; HF–NF intersection; Blockage coefficient

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