Low-Heat-Load-Vane Profile Optimization, Part 2: Short-Duration Shock-Tunnel Experiments

Complete knowledge of the heat transfer over the surfaces of turbine components within their harsh operating environments is key to knowing the durability of a given airfoil design. Here, a nominal turbine inlet vane was tested for unsteady-heat-load measurements in a low-aspect-ratio linear cascade. A new airfoil called the low-heat-load vane, designed specifically for a reduced heat load, was tested experimentally and unsteady-heat-load trends were compared with the nominal vane counterpart. The tests were performed in a reflected-shock tunnel to validate the flow solver and turbomachinery design system used to generate the new airfoil shape, for which special attention was paid to leading-edge and suction-side heat-flux characteristics. Results indicate an appreciable reduction in heat load relative to the nominal vane. This work lends credibility to designing turbine airfoils for durability with the same emphasis normally given to designing for aeroperformance.

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