Computational fluid dynamics (CFD) is widely used to simulate fluid flows in turbomachinery. A detailed CFD study was performed to enhance the design of an electrical submersible pump (ESP) manufactured by Baker Hughes. The pump has a special patented impeller design enabling it to handle up to 70% gas volume fraction (GVF).
A CFD-based design study was performed on the ESP diffuser (for the first time) to improve the pump’s performance and reduce losses. The CFD model was initially validated using experimental results. Different designs were simulated to reach the optimum design. Many factors affect pump performance, including flow separation losses in the stator (such as the number of blades, the meridional profile of the pump and the shape of the stator blades). In addition, a non-uniform flow while exiting one stage affects the rotor performance of the next stage. Therefore, improving the diffuser design improves the current stage performance as well as the performance of the next rotor. In this study, improved designs show that optimizing the stator design can increase the static pressure of the pump by 4% for single-phase flow, and 23% for two-phase flow in the simulated cases.