Finite element analysis for wellbore stability of transversely isotropic rock with hydraulic-mechanical-damage coupling  

作　　者：WANG YongLiang LIUZhanLi YANG HengLin ZHUANG Zhuo WANG YongLiang LIU ZhanLi YANG HengLin ZHUANG Zhuo(Applied Mechanics Laboratory, School of Aerospace Engineering, Tsinghua University, Beijing 100084, China;Zienkiewicz Centre for Computational Engineering & Energy Safety Research Institute, College of Engineering, Swansea University, Swansea SA2 8PP, UK;Drilling Research Institute, China National Petroleum Corporation, Beijing 100195, China)

机构地区：[1]Applied Mechanics Laboratory, School of Aerospace Engineering, Tsinghua University, Beijing 100084, China [2]Zienkiewicz Centre for Computational Engineering ＆ Energy Safely Research Institute, College of Engineering, Swansea University, Swansea SA2 8PP, UK [3]Drilling Research Institute, China National Petroleum Corporation, Beijing 100195, China

出　　处：《Science China(Technological Sciences)》2017年第1期133-145,共13页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.11372157&11302115);the Doctoral Fund of Ministry of Education of China(Grant No.20120002110075);the Foundation for the Author of National Excellent Doctoral Dissertation of China(Grant No.201326);the China Postdoctoral Science Foundation(Grant No.2015M571030)

摘　　要：The finite element analysis （FEA） technology by hydraulic-mechanical-damage （HMD） coupling is proposed in this paper for wellbore stability analysis of transversely isotropic rock, developed basing on the recently established FEA technology for iso- tropic rock. The finite element （FE） solutions of numerical wellbore model, damage tensor calculation and Pariseau strength criterion for transversely isotropic rock are developed for researching the wellbore failure characteristics and computing the collapse and fracture pressure of laminated rock as shale reservoirs. The classic Blot constitutive for rock as porous medium is introduced to establish a set of FE equations coupling with elastic solid deformation and seepage flow. To be in accord with the inclined wellbore situation, the coordinate transformation for global, wellbore, in-situ stress and transversely isotropic for- mation coordinate systems is established for describing the in-situ stress field and the results in laminated rock. To be in accord with the practical situation, a three-dimensional FIE model is developed, in which several other auxiliary technologies are com- prehensively utilized, e.g., the typical Weibull distribution function for heterogeneous material description and adaptive tech- nology for mesh refinement. The damage tensor calculation technology for transversely isotropic rock are realized from the well-developed continuum damage variable of isotropic rock. The rock is subsequently developed into a novel conceptual and practical model considering the stress and permeability with the damage. The proposed method utilizing Parisean strength cri- terion fully reflects the strength parameters parallel or perpendicular to bedding of the transversely isotropic rock. To this end, an effective and reliable numerically three-step FEA strategy is well established. Numerical examples are given to show that the proposed method can establish efficient and applicable FE model and be suitable for analyzing the state of pore pressure and s

关 键 词：finite element analysis wellbore stability transversely isotropic rock damage tensor hydraulic-mechanical-damagecoupling 

分 类 号：TE21[石油与天然气工程—油气井工程]