底部钻具组合的二重非线性有限元分析  

DOUBLE-NONLINEAR FINITE ELEMENT ANALYSIS OF BOTTOM HOLE ASSEMBLY

作　　者：孔凡忠[1] 郑小平[1] 姚振汉[1] 

机构地区：[1]清华大学工程力学系,北京100084

出　　处：《工程力学》2000年第6期32-40,共9页Engineering Mechanics

摘　　要：本文将弯曲井眼中的底部钻具组合(英文名称为Bottom Hole Assembly，简称BHA)作为空间梁来处理，在考虑几何非线性因素的基础上，导出了相应的有限元切向刚度矩阵。然后，利用“施加”与“放松”约束的方法处理了钻柱与井壁之间的接触非线性问题，并且考虑了钻柱与井壁之间摩擦力的影响。在此基础上，建立了对大曲率弯曲井眼中的钻柱进行二重非线性有限元分析的基本方程，以及相应的牛顿－拉斐逊迭代求解技术。最后，通过数值算例和工程算例证明了本文方法的可靠性，所得结果为大曲率井眼轨迹控制提供了参考依据。In this paper, Bottom Hole Assembly in a curved wellbore is treated as spatial elastic beam. On the basis of geometrically nonlinear strain analysis, tangent stiffness matrixes are deduced. Then the boundary nonlinear problem considering fiction force between drillstring and well wall has been dealt with by the method of 'applying' or 'deleting' constraints. The basic formulations for the double nonlinear finite element analysis of drillstring in the large curvature wellbore are set up, and the Newton-Raphson iteration method is employed to solve the non- linear equations. Numerical and engineering examples are studied to verify the reliability of the present method. The present work can provide useful reference for the large curvature wellbore trajectory prediction and simulation.

关 键 词：底部钻具组合 接触摩擦非线性 牛顿-拉斐逊方法 油气钻井工程 二重非线性有限元分析 

分 类 号：TE921.2[石油与天然气工程—石油机械设备]