摘要
构建大规模裂缝网络是干热岩有效开发的关键.借助径向井在诱导裂缝转向与多缝形成方面的优势,提出采用径向井压裂干热岩储层.基于温度-渗流-应力-损伤(THMD)耦合模型,考虑压裂过程中低温诱导热应力作用,首先探讨了干热岩径向井压裂裂缝扩展机理及径向井诱导作用下热应力与注入压力对应力场的扰动机制,随后分析了储层温度、径向井方位角对裂缝形态的影响规律.结果表明:采用径向井压裂干热岩在径向井的辅助冷却作用下低温诱导热应力加剧,径向井的存在有利于储层拉应力提升,干热岩径向井压裂与直井压裂相比损伤单元数增幅51.63%.基岩温度升高径向井引导裂缝偏转能力增强.径向井方位角增加有利于压裂损伤区域缝网沟通,降低流体流动阻抗.
The construction of large-scale fracture network is the key to efficient development of hot dry rock.Based on the advantages of radial well in fracture diversion inducing and multi-fracturing formation,radial well fracturing is proposed for the reconstruction of Hot Dry Rock(HDR)reservoir.Considering the effect of cryogenic induced thermal stress in hot reservoir fracturing,the Thermo-Hydro-Mechanical-Damage(THMD)coupling model is established.Firstly,the fracture propagation mechanism of radial well fracturing in HDR and the disturbance mechanism of thermal stress and injection pressure on stress field under the induction of radial well are discussed.Then,the influence of rock temperature and radial well azimuth on fracture morphology is analyzed.The results show that the cryogenic induced thermal stress is intensified under the auxiliary cooling effect of radial well,and the existence of radial well is conductive to the increase of tensile stress.Compared with vertical well fracturing,the number of damage units raised by 51.63%in radial well fracturing of HDR.With the increase of rock temperature,the ability of fracture diversion inducing in radial well fracturing is enhanced.The increase of azimuth angle of radial well is beneficial to communication of fracture network in fracturing damage zone,which can reduce the flow impedance of injected fluid.
作者
贺甲元
张伟
张乐
郭天魁
王春光
曲占庆
HE JiaYuan;ZHANG Wei;ZHANG Le;GUO TianKui;WANG ChunGuang;QU ZhanQing(Sinopec Petroleum Exploration and Production Research Institute,Beijing 100083,China;College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China;Key Laboratory of Unconventional Oil and Gas Development(China University of Petroleum(East China)),Ministry of Education,Qingdao 266580,China;New-Energy Development Center of Shengli Oilfield,Dongying 257001,China)
出处
《地球物理学进展》
CSCD
北大核心
2023年第1期20-30,共11页
Progress in Geophysics
基金
国家自然科学基金资助项目(42102338)
山东省自然科学基金项目(ZR2020QE115)
中国博士后科学基金资助项目(2022M712210)
中央高校基本科研业务费专项资金资助(27R1902010A)
中国石化科技部项目(P19035)联合资助。
关键词
干热岩
裂缝扩展
径向井压裂
岩石损伤
THMD耦合
Hot Dry Rock(HDR)
Fracture propagation
Radial well fracturing
Rock damage
Coupled THMD model
