Numerical investigation of wall shear stress under single-phase and two-phase flow in the electrical submersible pump

Abstract

The effects of the wall shear stress on an Electrical Submersible Pump (ESP) was investigated in this paper. A CFD model in ANSYS Fluent was proposed to simulate actual single-phase and two-phase flow. The bottom hole pressure was minimized by utilizing the artificial lift methods. The flowing fluids in pumps and pipes causes shear stress on surface interacting. In multiphase flow application pump damages on head degradation as well as shear stress affects. The K-ω turbulence model and the multiphase Mixture approach with the sliding technique used to solve the Navier-Stokes equation. To study the effects of gas-liquid (air-water) flow on the ESP and the pump handle ability, the rotation speeds were varied while the other parameters were kept constant. The rotation speeds simulated were at 500, 900, 1500, 2000 and 2500 rpm meanwhile the water flow rate and gas flow rate were kept constant with 20 L/min and 1% fraction, respectively. The results obtained show that as the rotation speeds were increased, the less concentration of the bubbles were observed, moreover the wall shear stress (WSS) increases. Although, the wall shear stress in both single-phase and two-phase flow were tend to increase as the blades length increased, however for the single-phase flow the WSS was found higher in all the simulated rotational speeds. © 2021, World Scientific and Engineering Academy and Society.

keywords: Cavitation; CFD; Electrical Submersible Pump; Gas Pocket; Mixture Model; Pump Head; Turbulence Model; Two-Phase Flow; Wall Shear Stress