Investigation Effect of Type and Diameter of Volute on the Efficiency of Centrifugal Reverse Pump at Different Operating Conditions

In radial turbines, two types of the radial and tangential volute are usually used in terms of their applications. In the application of the pump as turbine, the utilized type of radial or tangential volute is very important in terms of their operation areas. In this paper, the effect of the volute type and its diameter reduction as one of the effective parameters in turbine state was investigated. In this regard, PAT was designed with CFTurbo software, and mesh generation process was performed with ANSYS Meshing software, and by CFX software Analyzed with finite volume method approach and turbulent k-ω SST model, and the results of numerical simulation with the experimental results were compared and validation. Investigating the effect of volute type in turbine mode on hydraulic parameters and efficiency showed that when the flow rates is less than BEP point (Q<QBEP), the radial volute efficiency is 0.715% higher than the tangential volute, and when the flow rates is greater than the BEP point (Q>QBEP) use of tangential volute causes an increase in the efficiency up to 1.03% compared to the radial volute. The results of the reduction in the diameter of the volute indicate an increased of 4.05% of the efficiency at BEP point, of course in lower points of BEP point is more effective than higher points (Q<QBEP).