Numerical analyses of coupled thermo-mechanical behaviors of cement sheath in geothermal wells

作     者：Hao Wang Jinlin Wang Zhichao Zhang Xiaohui Cheng 

作者机构：State Key Laboratory of Coastal and Offshore EngineeringDalian University of TechnologyDalian 116024China School of Civil EngineeringChongqing UniversityChongqing 400045China Department of Civil EngineeringTsinghua UniversityBeijing 10084China 

出 版 物：《Underground Space》 (地下空间（英文）)

年 卷 期：2023年第8卷第1期

页      面：80-93页

核心收录：

学科分类：07[理学] 070204[理学-等离子体物理] 0702[理学-物理学] 

基　　金：the financial support from the 7 th Framework Program for Research of European Commission(Grant No.612665) National Natural Science Foundation of China(NSFC,Grant No.51778338) 

主　　题：Geothermal well Thermal-mechanical coupling Finite element analysis Constitutive model Cement sheath Thermodynamic theory 

摘      要：The stability of cement sheath under high temperature and high pressure is one of the most critical issues for the durability of geother-mal well *** this study,a two-dimensional plane-strain finite element code was developed to investigate the coupled thermo-mechanical behaviors of the casing-cement-formation *** from previous linear elastic analyses,a thermoelasto-plastic con-stitutive model based on the thermodynamic theory was adopted for the cement *** is shown that the finite element simulations using the proposed model provide a more accurate and realistic prediction of stress–strain responses of the cement sheath under high *** results demonstrate that the radial stress concentration and the tensile strain concentration occur at both the cement–casing interface and the cement–formation interface,where the cement sheath is most likely to *** strength and low stiff-ness in the cement sheath and the formation are preferred for the integrity of the *** large thermal cycles and large differences between the internal fluid pressure and the external pressure should be avoided during *** new code is an alternative tool for guiding the geothermal well *** finite element framework described herein is universal for other thermo-mechanical applications,such as energy foundations and energy tunnels.