EPJ Web of Conferences 67, 02104 (2014)
https://doi.org/10.1051/epjconf/20146702104

Experimental and numerical analysis of unsteady behaviour of high efficiency mixed-flow pump

¹ Centre of Hydraulic Research, J. Sigmunda 190, 783 49 Lutin, Czech Republic
² SIGMA Research and Development Institute, J. Sigmunda 79, 783 50 Lutin, Czech Republic
³ Slovak University of Technology in Bratislava, Faculty of Mechanical Engineering, Námestie Slobody 17, 812 31 Bratislava 1

^a Corresponding author: m.sedlar@sigma.cz

Published online: 25 March 2014

Abstract

This work deals with the experimental and numerical investigation of cavitating and noncavitating flow inside a mixed-flow pump and its influence on performance curves of this pump. The experimental research has been carried out in the closed horizontal loop with the main tank capacity of 35 m³. The loop is equipped with both the compressor and the vacuum pump capable of creating different pressure levels while maintaining constant volume flow rate. Pump investigated in this project has been equipped with transparent windows, which enabled the visualization of flow and cavitation phenomena for a wide range of flow conditions. A comprehensive CFD analysis of tested pump has been done both in the cavitating and noncavitating regimes. The ANSYS CFX commercial CFD package has been used to solve URANS equations together with the Rayleigh-Plesset model and the SST-SAS turbulence model. Both the experimental research and the CFD analysis have provided a good illustration of the flow structures inside the pump and their dynamics for a wide range of flow rates and NPSH values. Flow and cavitation instabilities have been detected at suboptimal flow rates which correspond to increased values of noise and vibrations. The calculated results agree well with the measurements.