11th European Conference on Turbomachinery Fluid dynamics & Thermodynamics
The paper presents the first experimental performance data for a mid-stage centrifugal compressor test rig built at RWTH Aachen University. The results provide an analysis of the operational and loss behavior and will be published in an open test case for validating numerical methods. The test rig was built to investigate the operational and loss behavior of a complete return channel in detail and is broadly introduced. The measurements described in this paper were designed based on numerical calculations. Further, the stage performance is analyzed based on a compressor map for design speed, supplemented by detailed measurements inside the diffusion system. The performance of the diffuser and the return channel are discussed separately. The significant influence of the return channel design on the overall stage efficiency and pressure build-up is emphasized. Additional angle measurements at the stage outlet provide details about the inflow to the potential next compressor stage.