The experimental program reported here was executed using full-scale vaneless counter-rotating engine hardware operating at nondimensionally scaled aerodynamic design point conditions. Measurements were obtained for three different pressure ratio values: design point, low pressure ratio, and high pressure ratio. For brevity, only the design point data will be presented in this paper. Time-averaged and time-resolved surface pressures on the high pressure turbine (HPT) vane, HPT blade, and low pressure turbine (LPT) blades are presented. Additionally, three-dimensional (3D) Navier-Stokes computational fluid dynamics (CFD) predictions are presented for comparison with experimental data. The results presented show that the predictions qualitatively capture the flowfield physics, but require some additional calibration to fully match experimental data quantitatively.

Experimental tests were performed at the USAF Turbine Research Facility (TRF) to obtain heat transfer and aerodynamic data on a first stage vane of a modern high pressure turbine. This is a transient blowdown facility that provides data from short duration tests. Data for a matrix of test conditions were obtained to document the effect of inlet Reynolds number, the stage pressure ratio across the vane, and the gas-to-wall temperature ratio. The objectives of these tests were to assess the capability of obtaining accurate aerodynamic total pressure loss measurements and airfoil static pressure measurements as well as determine the heat transfer coefficient distributions on the vanes. Results from these tests were compared to analytical predictions and are presented. The unique contribution of the work presented herein is: 1) demonstration of circumferential traversing temperature and pressure data in a short duration facility test, and 2) heat loss closure during a short duration test using heat flux gauges and the measured temperature loss. The transient heat loss during a short duration test is a fundamental requirement to determine turbine efficiency when work extraction is determined from the temperature drop across the turbine stage. Heat transfer data were acquired from heat flux gauges that were fabricated using thin-film sputtering techniques and placed on the airfoil surfaces. The surface temperature of the gauge was measured and heat flux was determined from a closed form transient semi-infinite solution that included the resistance of the heat flux gauge and the underlying metal substrate. Circumferentially, pressure measurements were obtained on the airfoil surfaces and on traversing rakes at the inlet and exit of the vane test section. Total and differential pressure rake instrumentation was required to obtain accurate aerodynamic loss measurements over a range of gas-to-wall temperature ratios.

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