High Resolution Probe Measurements in a Multi-Stage Turbine Rig

This paper introduces the Rotating Turbine Rig (RTR) and presents the results of its first measurement campaign. The turbine test facility, NG-Turb, situated at DLR Göttingen, is described and a detailed description of the RTR setup is given. The measurement equipment and its associated uncertainties are examined. The focus of the results presented is on the aerodynamic design point of the 2½ stage high-pressure turbine. A typical test day operation and its stability and repeatability of the operational points are presented. Additionally, the investigation delves into the homogeneity of inflow and outflow. The reproducibility of measurements across different test days is compared, thereby illustrating the consistency and reliability of the experimental data. Finally, inter-blade flow fields measured by pneumatic probes is presented. Specifically, the study of the flow structures associated with tip flow leakage, purge flows, and cooling flows, and their interactions with the main flow is described. The high-resolution data is used to foster the understanding of multi-stage turbine flow.