Flow Characteristics Beyond Time and Phase: A Modal Analysis of the Patterns in a Regenerative Pump

C2 - Numerical Methods

The purpose of this paper is to introduce the proper orthogonal decomposition (POD) as an efficient method to understand the complex flow behavior of fluid machinery in case of appearing periodicity. Despite progressively mature application for reduced-order-model approaches (ROM), only little attention is paid to POD as a tool for pattern identification and subsequent intensity quantification. The hidden beauty of this method for fluid/turbo machinery is emphasized in the present manuscript, with the main focus on a complementary discussion of conventional post processing (time and phase average, qualitative topology analysis) and the POD approach. The discussion is supported by high-speed 2D-3C PIV measurement data within the side channel of a regenerative pump, which reveals the interaction between the side channel and the impeller.