EXPERIMENTAL STUDY ON THE SPIRAL FLOW RESTRAINING ECCENTRIC WEAR OF THE SUCKER AND TUBING WITH PIV

To study the relationship between the state of fluid flow and the normal force applied to the sucker in the eccentric annulus of the polymer flooding oil recovery well, firstly the paper measures the axial flow and spiral flow produced in a simulated well, then studies the speed transient characteristics of the axial flow and the spiral flow in the eccentric annulus with narrow and wide gap under different mass concentrations of the polymer solution, and the axial velocity gradient of the axial flow and spiral flow is also compared with each other using the particle image velocimetry (PIV). The normal force of the eccentric rod of unit length is measured in different mass concentrations of the polymer solution media, also in the conditions of the axial flow and spiral flow using experimental device designed by our own. The results showed that, the axial velocity gradient is smaller than that of the axial flow in the eccentric annulus, and the decreasing magnitude of the axial velocity gradient in the narrow gap is larger than that in the wide gap; in the conditions of spiral flow, the normal force of the sucker of unit length is less than that in the axial flow. Using the method to generate the spiral flow can inhibit the sucker and tubing wear phenomenon in the polymer flooding oil recovery well.