旋转级次抽油杆柱动力学模型及其差分方程

建立了直井中用于驱动井下螺杆泵的旋转级次抽油杆柱扭转动力学分析模型 ,推导出了该模型的一种有限差分方程 ,并给出了方程的收敛条件 .模型中利用了级次抽油杆柱联结处扭矩及转角连续条件和转角的泰勒级数展开式 ,使该差分方程适合于级次抽油杆柱组合的情况 .这种模型及其差分方程配以一定的定解条件后 ,不仅可用于地面驱动螺杆泵抽油系统的杆柱组合优化设计、行为预测 ,也可用于该系统的工况诊断以及杆柱强度校核

Dynamic Model of Rotary Sucker Rod String and Its Finite Difference Equation

In this paper was established the twisting dynamic model of the rotary sucker rod string,which is used for driving downhole screw pump in a vertical well.A kind of finite difference equation of the model was also given.Because the continuous conditions of the torsion moment and torsion angle at the connects of the sucker rod string,and Taylor expansion of the torsion angle were used in the establish ment of the model,the difference equation can be used for the combined sucker rod strings of different material.Adding some definite conditions,the model and its difference equation can be used in the optimization design,behavoir prediction,working condition diagnosis and strength checking of the sucker rod string combination.