Aerodynamic Performance Measurement in a Fully Scaled Transient Turbine Test Facility

Abstract

The practical performance, both the efficiency and durability, of a High-Pressure (HP) turbine depends on many interrelated factors, including both the steady and unsteady aerodynamics and the heat transfer characteristics. The aerodynamic performance of new turbine designs has traditionally been tested in large scale steady flow rigs, but the testing is adiabatic, and the measurement of heat transfer is very difficult. This paper presents the results of turbine aerodynamic performance measurements at the Oxford Rotor Facility (ORF). Transient test facilities such as the Oxford Rotor allow the simultaneous study of turbine performance and heat transfer. The transient operation gives engine representative Mach number, Reynolds number and gas-to-wall temperature ratios, which are key to the aerothermodynamics of a highly-loaded, transonic, HP turbine stage. Time resolved experimental results are presented together with numerical CFD predictions over a 3% range of non-dimensional speed. The precision uncertainty of the measurements has been resolved to a level comparable with the state of the art in steady flow testing, in the region of ±0.3%.