Open Access

ARTICLE

Horizontal Well Interference Performance and Water Injection Huff and Puff Effect on Well Groups with Complex Fracture Networks: A Numerical Study

Haoyu Fu^1,2,3, Hua Liu^1,2, Xiaohu Hu^1,2, Lei Wang^1,2,3,*

1 State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, SINOPEC, Beijing, 100101, China
2 Sinopec Key Laboratory of Shale Oil/Gas Exploration and Production Technology, SINOPEC, Beijing, 100083, China
3 Key Laboratory of Tectonics and Petroleum Resources, Ministry of Education, China University of Geosciences, Wuhan, 430074, China

* Corresponding Author: Lei Wang. Email:

(This article belongs to the Special Issue: Modeling of Fluids Flow in Unconventional Reservoirs)

Computer Modeling in Engineering & Sciences 2023, 137(3), 2285-2309. https://doi.org/10.32604/cmes.2023.027996

Received 25 November 2022; Accepted 02 March 2023; Issue published 03 August 2023

Abstract

Well interference has become a common phenomenon with the increasing scale of horizontal well fracturing. Recent studies on well interference in horizontal wells do not properly reflect the physical model of the postfracturing well groups and the realistic fracturing process of infill wells. Establishing the correspondence between well interference causative factors and manifestations is of great significance for infill well deployment and secondary oil recovery. In this work, we develop a numerical model that considers low velocity non-Darcy seepage in shale reservoirs to study the inter-well interference phenomenon that occurs in the Santanghu field, and construct an explicit hydraulic fracture and complex natural fracture network model with an embedded discrete fracture model, focusing on the effect of fracture network morphology on well interactions. The model also considers a multi-segment wellbore model to accommodate the effect of inter-well crossflow on wellbore tubular flow. The changes in formation pressure and water saturation during fracturing are performed by controlling the injection pressure and water injection rate. The result shows that the shape of the fracture network generated by the infill well with the old well determines the subsequent fluid and oil-increasing performance of the disturbed well. The synergistic production or competitive relationship formed by fractures with different connectivity between the two wells determines the positive and negative effects of the interference. The paper also investigates the adaptation study of water injection huff and puff schemes for well groups with different connectivity, and demonstrated a potential yield increase of up to 10.85% under adaptation injection. This method of identifying well interference based on the production dynamics of affected wells and the subsequent corresponding water injection method provides valuable references for the selection of secondary oil recovery measures.

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