Sheldon Wang, Abbey Henderson, Sean T. Aleman and Trent Creacy, Midwestern State University
Lynn Rowlan and Carrie-Anne Taylor, Echometer Company
The issues of leakage with respect to the clearance between the pump plunger outer diameter (OD) and the pump barrel inner diameter (ID) and other operation conditions have been revisited in this paper using viscoelastic models. Both Poiseuille flow rate due to the pressure difference and Couette flow rate due to the plunger motion have been considered. The purpose of this study is to better understand the nature of the leakage with respect to pressure difference, eccentricity, and motion related to the plunger of typical sucker rod pump systems and gradually to link the downhole dynamics and motions with the surface pump jack unit. More specifically, based on the newly derived relaxation time scales for transient solutions of the governing Navier-Stokes equations, the quasi-static nature of relevant measurement techniques is confirmed for current production systems.