THE INFLUENCE OF THE NUMBER OF BLADES IN THE SECTOR MODELED BY CFD METHODS ON THE FLOW CHARACTERISTICS OF A CENTRIFUGAL PUMP

Abstract

is driven by the need for efficient and reliable pump turbines for pumped storage power plants, which ensure the flexibility of the power system in theface of an increasing share of renewable energy sources. The model's geometry is based on high-pressure pumped storage power plant data. VistaCPD, BladeGen, and TurboGrid tools were used to build the computational domain. The modeling was performed using the RANS approach and theSST turbulence model. The main attention is paid to the influence of the number of blades in the computational model sector on the calculation results. The complete model with seven blades provided the most accurate pressure and velocity distribution reproduction, but it requires significantcomputational resources. Reducing the number of blades to one leads to substantial distortions in the hydrodynamic flow pattern. The model with threeblades demonstrated an optimal compromise between accuracy and computational efficiency: the integrated characteristics, including head andefficiency, differ from the complete model by less than 1 %. The results help optimize the design process of reversible pump turbines, allowing for areduction in modeling time without a significant loss of accuracy. Comparison of the characteristics shows that in the case of a single-blade model, thepoint of highest efficiency shifts towards higher flow rates. At the same time, the pump head in this model is higher over the entire flow range compared to the more accurate calculation options.