中国石油大学学报（自然科学版）2026，Vol.50Issue(2)：85-95,11.DOI:10.3969/j.issn.1673-5005.2026.02.009
干热岩径向井压裂裂缝起裂与扩展数值模拟
Numerical simulation of fracture initiation and propagation characteristics in radial borehole fracturing of hot dry rocks
摘要
Abstract
Hydraulic fracturing is the core technology for the efficient development of enhanced geothermal systems(EGS),but it faces with several significant challenges,including single fracture,difficulty in controlling fracture propagation,and poor connectivity between injection and production wells.To address these issues,a new approach was proposed to steer the directional propagation of hydraulic fractures using radial wellbores in this study.A three-dimensional thermo-hydro-mechani-cal coupled fracture propagation numerical model based on a discrete lattice method was established to elucidate the initiation and propagation characteristics of fractures in hot dry rock(HDR)for radial borehole fracturing and vertical well fracturing.The effects of rock temperature,in-situ stress,injection rate,and fluid viscosity on the directional propagation of fractures guided by radial boreholes were investigated.The results show that the fracture morphology in radial borehole fracturing is dominantly controlled by the re-formed stress distribution around the radial borehole,with fractures initiating and propagating directionally along the radial borehole.In contrast,fractures in vertical well fracturing are mainly influenced by the original in-situ stress distribution and tend to propagate along the maximum principal stress direction.A greater temperature differ-ence between fracturing fluid and rock can enhance thermal stress,facilitating the formation of a complex fracture network,while the steering effect of the radial borehole on fracture propagation may diminish under these conditions.When the in-situ stress difference coefficient ranges from 0 to 0.4,the reformed stress distribution around the radial borehole is large,it can facilitate the formation of multiple directional main fractures.Increasing the injection rate and viscosity of the fracturing fluid can strengthen the steering effect of radial borehole on fracture and significantly increase fracture complexity.关键词
干热岩/径向井压裂/热流固耦合模型/热应力/裂缝扩展模式Key words
hot dry rock/radial borehole fracturing/thermal-hydraulic-mechanical coupling model/thermal stress/fracture propagation patterns分类
能源科技引用本文复制引用
邹文超,武晓光,黄中伟,李根生,史怀忠,张旭,王小华..干热岩径向井压裂裂缝起裂与扩展数值模拟[J].中国石油大学学报（自然科学版）,2026,50(2):85-95,11.基金项目
国家自然科学基金重点国际(地区)合作与交流项目(52020105001) （地区）
国家自然科学基金创新研究群体项目(52421002) （52421002）
国家自然科学基金青年科学基金项目(5230040287) （5230040287）
