储气库注采管柱屈曲后表面半椭圆裂纹力学分析  

Mechanical analysis of semi-elliptical cracks on surface of gas storageinjection-production pipe string after buckling

作　　者：张强[1] 张罡 郭爽 赵栋 吕磊 ZHANG Qiang;ZHANG Gang;GUO Shuang;ZHAO Dong;LÜLei(School of Mechanical Science and Engineering,Northeast Petroleum University,Daqing 163318,China)

机构地区：[1]东北石油大学机械科学与工程学院,黑龙江大庆163318

出　　处：《塑性工程学报》2024年第6期208-216,共9页Journal of Plasticity Engineering

基　　金：黑龙江省自然科学基金资助项目(LH2020A001)。

摘　　要：采用有限元方法,研究了注采管柱屈曲后表面半椭圆裂纹的应力强度因子K_(Ι)和J积分。首先,由于储气库注采管柱是长直圆管结构,通过建立含外表面裂纹直管的有限元模型,对其进行有限元验证。然后,基于子模型法,建立了管柱屈曲后裂纹力学计算模型,计算了屈曲后不同裂纹形状参数、裂纹相对深度和轴线夹角下的应力强度因子K_(Ι)和J积分,分析了管柱不同螺距数对K_(Ι)和J积分的影响规律。结果表明,有限元法在计算应力强度因子时精度较高,造成有限元法误差明显的主要因素是网格尺寸和裂纹前缘网格划分份数;管柱螺旋屈曲后,K_(Ι)和J积分随裂纹形状参数的增加而减小,随裂纹相对深度的增加而增大;随着注采管柱屈曲螺距数以及轴线夹角的增加,K_(Ι)和J积分均呈增长趋势,且裂纹为周向裂纹时的增长速率最大。The stress intensity factor K_(Ι)and J integral of the semi-elliptical crack on the surface of the injection-production pipe string after buckling were studied by using the finite element method.First,since the gas storage injection-production pipe string is a long straight circular pipe structure,the finite element model of the straight pipe with cracks on the outer surface was established to conduct finite element verification.Then,based on the submodel method,the crack mechanical calculation model after pipe string buckling was established,and the stress intensity factors K_(Ι)and J integrals with different crack shape parameters,crack relative depths and axis angles after buckling were calculated,and the effect low of different pitch numbers of pipe string on K1 and J integrals was analyzed.The results show that the finite element method has high accuracy in calculating the stress intensity factor,and the main factors causing the obvious error of the finite element method are the grid size and the number of crack leading edge meshing.After helical buckling of the pipe string,K_(Ι)and J integral decrese with the increase of shape parameter,and increase with the increase of or crack relative depth;with the increase of the number of buckling pitches of the injection-production pipe string as well as the axial angle,both K_(Ι)and J integral tend to increase,and the increase rate is the largest when the crack is a circumferential crack.

关 键 词：有限元 注采管柱 裂纹 螺旋屈曲 应力强度因子 J积分 

分 类 号：TE972[石油与天然气工程—石油机械设备]