Numerical investigation of the flow in a multistage electric submersible pump

This article presents a numerical study on the flow in a multistage, mixed-type Electric Submersible Pump (ESP). Several details about the application of a computational fluid dynamics (CFD) program based on the finite volume method for the numerical solution of the flow inside a multistage pump are presented. At first, the numerical model is used to evaluate the influence of turbulence models and the number of stages on performance. Next, numerical head curves for a three-stage ESP are compared with experimental data from literature for a pump of same model and number of stages, for which a good agreement is found. Then, relevant flow characteristics inside the pump stages are compared for different flow rates, such as the restriction of the net flow area at the interface between diffusers and impellers due to a reverse flow structure. Some transient flow features inside the pump are also discussed. This work can give useful insight on the application of numerical simulations of the flow in multistage, mixed-type ESPs, for which there are few works in literature. It can also contribute to expand the understanding of the flow in this type of pump, guide design optimizations and provide a basis to investigate the flow in more realistic ESP applications, such as in boosting viscous liquids and multiphase flows.