固液耦合工况下钻柱的扭振频率分析

Torsional Vibration Analysis of Drill String by FSI

采用ANSYS有限元分析软件对钻柱在固液耦合工况下的扭振频率进行分析,得到了钻柱的前5阶扭转振动固有振型,并对钻井液、钻铤长度、钻柱长度等因素对钻柱各阶扭振频率的影响进行研究。结果表明:钻铤长度、钻柱长度均对钻柱的扭振频率有较大的影响,可以忽略井筒中钻井液、轴向载荷等因素对钻柱扭转振动的影响。

The torsional vibration intrinsic frequencies of drill string are analyzed by FSI. The rela tionship was analyzed between the drill string torsional vibration intrinsic frequencies and mud, length of drill pipes,length of drill collars by using of software ANASYS. And one to five step in- trinsic frequencies of drill string are gained. The results of the study show that the length of drill pipes and drill collars have a major influence over drill string torsional vibration intrinsic frequen- cies.