Effects of tip clearance on energy performance of three-stage electrical submersible pump

Abstract

In order to investigate the influence of tip clearance on the energy performance of electrical submersible pump (ESP), numerical simulation and experimental study were carried out. The three-dimensional transient Reynolds-Averaged Navier–Stokes (RANS) equation is solved by using the ANSYS CFX software. The experimental results were used to verify the reliability of the numerical method. The results shown that the increase of tip clearance leads to the decrease of energy performance. The increase of tip clearance leads to a proportional drop in energy performance under part-load flow rate conditions, while the increase of tip clearance leads to a significant loss under large flow rate conditions due to increased leakage. The rotor-stator interaction between the impeller and the diffuser is the main factor for the enhanced turbulence at part-load flow rate conditions, resulting in energy losses. The maximum turbulence intensity along the axial direction in the tip clearance is 4.4 times and 4.7 times of the minimum turbulence intensity at rated flow rate 1.0Qdes and large flow rate 1.4 Qdes operating conditions, respectively. The results could be referred to predict the internal flow loss and optimize the design of ESPs.