Investigations on unsteady flow within a stationary passage of a pressure wave exchanger, by means of PIV measurements and CFD calculations

[Display omitted] •Pressure exchanger was redesigned in purpose to perform flow visualizations.•Major flow features of a pressure exchanger were presented in form of PIV analysis.•Validation of numerical calculations proved good agreement with experimental data.•PIV and CFD data proved that the designed device realized the assumed working cycle. This paper presents results of investigations focused on a pressure wave exchanger demonstrator, constructed at the Aerodynamics Division at Warsaw University of Technology. Main flow features of the device were analyzed and experimental data was collected in order to perform validation of CFD calculations. Three different turbulence models (Standard-k-ω, SST-k-ω and SST-SAS) were used in simulations and tested in unsteady conditions. Data in form of: velocity field, shape and position of the contact surface between the driving and the driven medium served to perform comparison between PIV measurements and numerical calculations, which revealed that the best correlation between experiments and numerical data was obtained with SST-SAS turbulence model.