CFD based evaluation of conventional electrical submersible pump for high-speed application

Abstract Fluctuations in oil prices have negatively affected the petroleum industry, prompting to look for innovative ways to optimize oil recovery. One of the current approaches to optimize oil production is to employ high-speed ESPs with Permanent Magnet Motors (PMM) that allow reducing the pump size while increasing the operating envelop. Standard affinity laws are a useful tool to provide a preliminary estimate of common pump performance. However, there is a need to understand the detailed variation in the flow variables and losses incurring due to fluid-geometry interactions at high rotational speeds. To evaluate the hydraulic performance of a mixed flow pump, Computational Fluid Dynamics (CFD) simulations were performed at rotational speeds ranging from 3600 rpm to 20000 rpm using fluids with different viscosities. Fluid behavior is studied by observing the change in flow parameters with rotational speed. Similitude analysis is utilized to characterize the pump performance. The numerical results yielded improved pump hydraulic performance with an increase in rotational speeds which is attributed to reduced separation losses mainly in the diffuser section. Research is concluded with further evaluation of the complete stage including secondary leakage flow path on flow variables and axial thrust forces.