地面驱动螺杆泵采油系统管道内流体摩阻分析

Analysis of frictional resistance of flow in annulus of surface driven screw pump system.

运用流体力学有关理论， 对地面驱动螺杆泵采油系统环空管道结构参数和螺杆泵转速对流体摩阻的影响进行了分析。分析结果表明， 当油管直径一定时， 过大的抽油杆直径会使抽油杆柱旋转所受的油液摩阻及油液流动摩阻增大； 泵的转速过高会使抽油杆柱旋转所受油液摩阻及油液流动摩阻增大。建议在满足抽油杆强度及其它条件下尽可能采用小直径抽油杆； 在满足泵排量、泵效及其它条件下尽量不要使泵转速过高。合理选择抽油杆直径和泵转速将显著降低地面驱动螺杆泵系统总的能量损失。

By using the theory of fluid mechanics, the influence of structural parameters of the annulus of the surface driven screw pump system and rotational speed of screw pump on the frictional resistance of the flow in the annulus is analyzed. When the tubing diameter is constant, excessive rod diameter or pump rotational speed will result in an increase of oil fliud frictional resistance on the rotary rod string and oil fluid flow frictional resistance. Therefore sucker rod of small diameter should be adopted as the strength of sucker rod is assured and other conditions are satisfied; excessive rotational speed of the pump should be avoided as the pump displacement and efficiency and other conditions are satisfied. Total energy loss of the screw pump system will be reduced remarkably if proper rod diameter and pump speed are selected.