Stress-dependent unstable dynamic propagation of multiple hydraulic fractures: a review of stress shadow effects and continuum-discontinuum methods
ISSN: 0264-4401
Article publication date: 27 January 2023
Issue publication date: 14 February 2023
Abstract
Purpose
The unstable dynamic propagation of multistage hydrofracturing fractures leads to uneven development of the fracture network and research on the mechanism controlling this phenomenon indicates that the stress shadow effects around the fractures are the main mechanism causing this behaviour. Further studies and simulations of the stress shadow effects are necessary to understand the controlling mechanism and evaluate the fracturing effect.
Design/methodology/approach
In the process of stress-dependent unstable dynamic propagation of fractures, there are both continuous stress fields and discontinuous fractures; therefore, in order to study the stress-dependent unstable dynamic propagation of multistage fracture networks, a series of continuum-discontinuum numerical methods and models are reviewed, including the well-developed extended finite element method, displacement discontinuity method, boundary element method and finite element-discrete element method.
Findings
The superposition of the surrounding stress field during fracture propagation causes different degrees of stress shadow effects between fractures and the main controlling factors of stress shadow effects are fracture initiation sequence, perforation cluster spacing and well spacing. The perforation cluster spacing varies with the initiation sequence, resulting in different stress shadow effects between fractures; for example, the smaller the perforation cluster spacing and well spacing are, the stronger the stress shadow effects are and the more seriously the fracture propagation inhibition arises. Moreover, as the spacing of perforation clusters and well spacing increases, the stress shadow effects decrease and the fracture propagation follows an almost straight pattern. In addition, the computed results of the dynamic distribution of stress-dependent unstable dynamic propagation of fractures under different stress fields are summarised.
Originality/value
A state-of-art review of stress shadow effects and continuum-discontinuum methods for stress-dependent unstable dynamic propagation of multiple hydraulic fractures are well summarized and analysed. This paper can provide a reference for those engaged in the research of unstable dynamic propagation of multiple hydraulic structures and have a comprehensive grasp of the research in this field.
Keywords
Acknowledgements
The authors gratefully acknowledge financial support from the National Natural Science Foundation of China (grants 41877275 and 51608301), Beijing Natural Science Foundation (grant 212004), Open Fund of Tianjin Key Lab of Soft Soil Characteristics and Engineering Environment (grant 2017SCEEKL003), Yue Qi Young Scholar Project Foundation of China University of Mining and Technology, Beijing (grant 2019QN14), Fundamental Research Funds for the Central Universities, Ministry of Education of China (grant 2019QL02) and Teaching Reform and Research Projects of Undergraduate Education of China University of Mining and Technology, Beijing (grants J210613, J200709 and J190701).
Citation
Wang, Y. and Liu, N. (2023), "Stress-dependent unstable dynamic propagation of multiple hydraulic fractures: a review of stress shadow effects and continuum-discontinuum methods", Engineering Computations, Vol. 40 No. 1, pp. 149-190. https://doi.org/10.1108/EC-05-2022-0299
Publisher
:Emerald Publishing Limited
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