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As pumps are used frequently in industrial plants, their performance improvement is important. In this study, performance improvement of centrifugal pumps by application of splitter blades have been investigated both numerically and experimentally. Radial impellers with different length of splitter blades have been manufactured and tested to obtain performance charts. On the other hand, the flow in impeller and volute has been investigated numerically by ANSYS-CFX commercial code. Numerical study has been done using Finite volume method and k-ωSST turbulence model. Rotating and stationary frames have been used to analyze flow in impeller and volute respectively and the results have been coupled by Frozen Rotor. Three impellers with the lengths of splitter blades equal to 0, 33% and 66% of original blades were tested. Results show head increase when the splitter blades added while the amount of increase depends on the splitter blades length. At BEP (Best Efficiency Point) the maximum head increase was reported for impeller type three (the length of splitters equal to 66% of original blades) about 10.5 percent. It should be noted that as the capacity tends to BEP, the effect of splitter blades is more significant.

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Centrifugal pumps as a heart of the system which are used to move fluids are used widely in most of the industries and have considerable contribution in the amount of energy consumption, so improving of their performance has been attended for researchers .In this paper the aim of studying is the effect of double splitter blades on pump’s performance numerically and experimentally. Three type impellers have been made as experimental investigation. Pump with this impellers is tested and extracted the performance curve. Also, for investigation of the flow pump has been simulated numerically by ANSYS-CFX commercial code. Numerical method of finite volume with k-ω SST turbulence model for numerical analysis. Numerical and experimental results show reasonable agreement that increasing of head and variation of NPSHR due to adding of double splitter blades. The maximum head increased was obtained related to third type of Impeller about 6.33 percent. Furthermore, third type is selected as best impeller. Also, it is observed that around point of designing of pump the effect of double splitter blades on pump’s performance is more significant and deviation from this point will decrease the effect of it.