非均匀地应力场中井眼缩径的粘弹性数值模拟  

Numerical Viscoelastic Simulation of Wellbore Shrinkage in Non-uniform In-situ Stress

作　　者：侯广君[1] 窦益华[2] 王耀锋[2] 

机构地区：[1]大庆油田公司,黑龙江大庆163712 [2]西安石油大学机械工程学院,陕西西安710065

出　　处：《内蒙古石油化工》2009年第18期137-140,共4页Inner Mongolia Petrochemical Industry

摘　　要：采用AN SYS有限元软件将盐膏层模拟为三单元流变模型,系统地研究了非均匀地应力场中钻井液密度与井眼扩大系数对井眼尺寸的影响,实例分析表明:非均匀地应力场中井眼不再是规则的圆形而是椭圆形;井眼变化值在X方向最大,Y方向最小;X方向井眼半径伸缩量随着钻井液密度的增大而减少,随着井眼扩大系数的增大而增大;与井眼扩大系数相比,Y方向井眼半径伸缩量受钻井液密度的影响比较大:当钻井液密度1.6g/cm3时,Y方向为井眼缩小,钻井液密度1.8g/cm3时,Y方向为井眼扩大。The effect of density of drilling mud and expansion coefficient hole on wellbore shrinkage was analyzed assuming that the creep of salt rock is three element rheological model adopted ANSYS finite element software. A numerical example demonstrates that wellbore is ellipse rather than circle on the condition that non--uniform in--situ stress; The largest values of wellbore shrinkage are obtained at the X direction, but the minimum values locate at the Y direction; The values of wellbore shrinkage at the X direction is decrease with the increase of density of drilling mud and increase with the increase of expansion coefficient hole. The values of wellbore shrinkage at the Y direction is mainly affected by density of drilling mud compared with expansion coefficient hole. The wellbore of the Y direction will be narrow when density of drilling mud less than 1.6g/cm^3 and will be enlarge when density of drilling mud greater than or equal to 1. 8g/cm^3.

关 键 词：井眼缩径 钻井液密度 粘弹性分析 非均匀地应力场 三单元流变模型 

分 类 号：TE22[石油与天然气工程—油气井工程] TD311[矿业工程—矿井建设]