Open Access

ARTICLE

Modeling of Thermal Shock-Induced Fracture Propagation Based on Phase-Field Approach

Zhuang Liu^1,*, Tingen Fan¹, Qianli Lu², Jianchun Guo², Renfeng Yang¹, Haifeng Wang¹

1 CNOOC Research Institute Ltd., Beijing, 100028, China
2 State Key Laboratory of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, China

* Corresponding Author: Zhuang Liu. Email:

Fluid Dynamics & Materials Processing 2025, 21(4), 851-876. https://doi.org/10.32604/fdmp.2024.056729

Received 29 July 2024; Accepted 18 November 2024; Issue published 06 May 2025

Abstract

Thermal shock damage in deep shale hydraulic fracturing can impact fracture propagation behaviors, potentially leading to the formation of complex fractures and enhancing gas recovery. This study introduces a thermal-hydraulic-mechnical (THM) coupled fracture propagation model relying on the phase field method to simulate thermal shock-induced fracturing in the deep shale considering dynamic temperature conditions. The validity of this model is confirmed through comparison of experimental and numerical results concerning the THM-coupled stress field and thermal cracking. Special attention is paid to the interaction of thermal shock-induced fractures in deep shale that contains weak planes. The results indicate that thermal shock-induced stress significantly amplifies the tensile stress range and deteriorates rock strength, resulting in a multi-point failure pattern within a fracture. The thermal shock damage degree is closely related to the fracture cooling efficiency, suggesting that considering downhole temperature conditions in THM-coupled fracture stress field calculations is advisable. Thermal shock can activate pre-existing natural fractures and enhance the penetration ability of hydraulic fractures, thereby leading to a fracture network.

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Keywords

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