The paper refers to the analysis of interactions between the impeller and the vaned diffuser based on the air model of a radial flow pump. The study deals with a numerical simulation of the flow for a full 360° entire impeller and diffuser. The task is carried out closely under the design operating conditions and for one particular position of the impeller blade with respect to the diffuser frame. Among all the results, the focus is mainly on the flow pattern at the exit part inside the impeller facing the diffuser vanes. The results are compared to the available PIV measurements. centrifugal pump, impeller, vaned diffuser, rotor-stator interaction

No abstract

PIV measurements were performed at mid hub to shroud section inside the impeller of a vaned diffuser pump model working with air. The measurements were restricted to the outlet section of the impeller where the diffuser blades interacted with the impeller flow. Each PIV measuring plane was related to one particular impeller blade to blade channel and analysed according to different relative positions of the vaned diffuser. Two frame change models were considered: the so-called frozen rotor approach for different impeller passage positions relative to the vaned diffuser and a fully unsteady calculation of the whole pump. Comparisons between numerical and experimental results are presented and discussed for a specific mass flow rate corresponding to an off-design point for the impeller and a design point for the vaned diffuser.

The paper refers to the analysis of interactions between the impeller and the vaned diffuser on the air model of a radial flow pump. The study deals with a numerical simulation of the flow for a full 360 • entire impeller and diffuser. The task is carried out close to design operating conditions and for one particular position of the impeller blade with respect to diffuser frame. Among all the results, it has been decided to mainly focus on the flow pattern at the exit part inside the impeller coming from the diffuser vanes interactions. The results are compared to the available PIV measurements.