摘要
针对斜直井内钻柱在自重和上部压力共同作用下的屈曲分析,用Ritz法研究了端部约束方程的合理性。钻柱上端周向自由,下端铰支。结果发现:不同的端部边界约束方程所对应的屈曲载荷明显不同。根据能量泛函取驻立值时所必须满足的自然边界条件、井眼内钻柱的实际工作状况以及已有的实验结果,给出了钻柱屈曲分析时较为合理的端部边界约束方程。
The rationality of end constraint equations on buckling loads of a drillstring in an inclined wellbore is investigated. The lower end of the drillstring is supported by hinge while the upper end can move freely in the circumferential direction of the wellbore. The drillstring buckles under the action of its self-weight and a compressive force applied at its upper end. Buckling loads of the drillstring are calculated by using the Ritz method. It is found that buckling loads corresponding to the different boundary constraint equations are quite different. To ensure the consistency of the minimum of energy functional with its corresponding equilibrium equation eigenvalue, some essential boundary conditions have to be included. A set of more reasonable end constraint equations are given for buckling analysis of drillstrings, based on the actual working conditions and the existing experimental results.
出处
《工程力学》
EI
CSCD
北大核心
2008年第5期227-230,共4页
Engineering Mechanics
基金
江苏省高校自然科学基金(05KJB410015)
关键词
屈曲
非线性
约束方程
弹性细杆
钻柱
buckling
nonlinearity
constraint equations
elastic thin rods
drillstrings
作者简介
谈梅兰（1959-），女，江苏溧阳人，副教授，博士，从事工程问题力学计算建模（E-mail：tanmeilan@gmail．com）.
何小宝（1979-），男，江苏淮安人，硕士生，从事工程问题力学计算建模（E-mail：hxb1979@gmail.com）.
王鑫伟（1948-），男，江苏苏州人，教授，博士，从事数值计算研究（E-mail：wangx@nuaa．edu.cn）．
