基于振动力学的抽油杆柱传动效率数值仿真研究

抽油杆柱是抽油机井井下系统的主要组成之一,其传动效率一直被人们所忽视。由于抽油杆柱的细长结构,在传动载荷过程中引起较大的振动而消耗能量。根据振动理论,在考虑抽油杆柱初始几何缺陷条件下,建立抽油杆柱动态失稳的力学模型,采用间隙元理论,建立抽油杆与油管的动态碰撞接触边界,应用数值求解技术对抽油杆柱三维振动进行模拟,获得抽油杆柱的传动效率。将计算结果与试验井测试结果进行对比,两者具有较好的一致性,同时分析了杆柱传动效率与相关参数的关系,定量给出了对杆柱传动的效率影响,为提高井下效率奠定了理论基础。

Study on Transmission Efficiency Numerical Simulation of Rod String Based on Vibration Mechanics

The sucker rod string is one of the main components of the underground system of pumped well of pumping unit, its transmission efficiency has been neglected. In the process of transmitting load, the slender structure of the sucker rod string caused so large vibration that con-sumed more energy. Based on vibration theory and considering the conditions of the sucker rod string initial geometric imperfections, the sucker rod string dynamic instability of mechanical mod- el was established. Adopting gap element theory, the dynamic collision of the sucker rod and tub- ing contact boundary was established as well, by using numerical solution techniques to simulate three-dimensional vibration on the sucker rod string, and subsequently achieving transmission effi-ciency of sucker rod sting. Comparing the calculation results with the test results of the test wells, both can be concluded that they have better consistency. Analyzing the relationship of the transmission transmlsslon cleney. efficiency of the rod string and re efficiency on the rod string,these lai levant parameters to d the theoretical foundation tify influence of the of underground effi-ciency.