摘要
应用有限元法,考虑地层的层理性,假设地层为横观各向同性的,根据弹性理论,对下部钻具组合及地层进行三维分析。把钻柱及相关地层作为整体考虑,钻柱部分采用三维梁单元,地层部分采用六面体等参单元附以四面体单元填充,通过适当的简化和处理,解决了微机内存不够的困难。编制了相应的计算程序,应用该程序,可以得到不同的地层倾角和地层倾向变化时钻头侧向力(并斜力和方位力)的变化情况。给出地层对钻头侧向力影响的定量解答。
In light of the theory of elasticity, threedimensionalanalysis of Bottom-Hole Assembly and transversely isotropic stratum is made with finite element method. Drill collars and the stratum are considered as a whole in order to accurately reflect the actual conditions. By assigning space beam elements in drill collars and 8-node hexahedron isopara metric element and a few tetrahedron elments in the stratum, the problem of limited memory of microcomputer is solved through suitable simplification and treatment. The computer program is given in the paper. The changes of bit-lateral force may be obtained at different dip angle and dip direction, and quantitative solutions of the influence of stratum anisotropy on bit-lateral forces stratum are given.
出处
《石油大学学报（自然科学版）》
CSCD
1990年第4期43-50,共8页
Journal of the University of Petroleum,China(Edition of Natural Science)
基金
本文为"七五"国家重点科技攻关课题"定向井井眼轨迹控制"的一部分
关键词
地层
各向异性
钻头
侧向力
有限元
Finite element method
Drill collars
Transversely isotro-pic stratum
Bit-lateral forces
Computer program
