Flow in a turbine duct is highly complex, influenced by the upstream turbine stage flow structures, including tip leakage flow and non-uniformities originating from the upstream HP vane and rotor. The complexity of the flow makes the prediction using CFD methods difficult, hence there exists a need for experimental validation. This paper presents a new design of an intermediate turbine duct with a structural vane that has been designed, manufactured and integrated into the Oxford Turbine Research Facility. This is a short duration high speed test facility enabling the use of an engine sized turbine, operating at the correct non-dimensional parameters relevant for aerodynamic and heat transfer measurements. The current configuration consists of a HP stage and a downstream duct including a low-aspect ratio vane, representative for a counter rotating turbine configuration. Aerodynamic and heat transfer measurements are conducted to generate a database with which current CFD methods can be validated. The instrumentation presented here includes static pressure tappings and thin film heat transfer gauges on the ITD vane surface and endwalls. The time averaged measurements show the impact of different clocking positions of the ITD vane with respect to the upstream HP vane. This demonstrates the requirements of addressing the influence of vane counts and stator-stator clocking when designing new components. The measurements are compared with CFD predictions.
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