抽油杆柱有限元动力方程的差分解及其收敛性

根据有杆泵抽油系统工作过程所对应的力学行为特征，建立了基于有限元理论的抽油杆柱动力控制方程；针对系统工况诊断这一非常规有限元动力求解问题，提出了适合于杆柱对角线型质量矩阵的有限元──有限差分解法；这种方法的优点在于其适应性强，可以考虑抽油杆接箍的影响并能较方便地处理级次杆连接处的力和位移连续条件．还从理论上证明了求解方法的无条件收敛性，并已经油田近２００口油井实际数据验证．最后给出了以文中方法为基础的计算机智能诊断软件对两口油井工况进行诊断的结果．

The Difference Method for Solving Finite Element Dynamics Equation of the Sucker-Rods and Its Convergence

In view of the Mechanical behaviors of the.sucker-rod pumping(SRP)system,a dynamics governing equation of the sucker rod on the basis of the finite element theory was set up.In order to solve the abnomal finite element dynamics problem-working condition diagnosis of the SRP system,finite difference methodis put forward,which is suitable for the finite element of diagnal typed mass matrix.The merites of the methodare its strong daptability and it takes the effects of the collars into consideration,and can Conveniently deal withthe continuity condition of the force and displacement at the connections of the tapered rod strings.The unconditional convergence of this method has been proved theoretically in this paper and verified by actual information from almost 200 wells.In the end.the diagnosed results of two wells by computer intellengence diagnosissoftware based on the method of the p aper are presented.