Adiabatic wall temperature evaluation in a high speed turbine

Engine development requires accurate estimates of the heat loads. Estimates of the convective heat fluxes are particularly vital to assess the thermomechanical integrity of the turbomachinery components. This paper reports an experimental heat transfer research in a one and a half turbine stage, composed of a high-pressure turbine and a low-pressure vane. Measurements were performed in a compression tube facility at the von Karman Institute, able to reproduce engine representative Reynolds and Mach numbers. Double-layered thin film gauges were used to monitor the time-dependent temperature distribution around the airfoil. Several tests at different metal temperatures were performed to derive the adiabatic wall temperature. This research allowed quantifying the independent effects on the unsteady heat flux of the gas temperature fluctuations and boundary layer unsteadiness. © 2012 American Society of Mechanical Engineers.