Low-Heat-Load-Vane Profile Optimization, Part 1: Code Validation and Airfoil Redesign

Historically, there has been a distinct difference between the design of turbomachinery airfoils for aerodynamic performance and that for durability. However, future aeroengine systems will require ever-increasing levels of turbine inlettemperature, causing the durability andreliability of components to be anever-more-important design concern. As a result, the need to incorporate heat-transfer predictions into traditional aerodynamic design and optimizationsystems presents itself.Thefollowing isaneffortto designaminimized-heat-load airfoilwith reputable aerodynamics. A Reynolds-averaged Navier–Stokes flow solver is validated over different flow regimes and various boundary conditions against extensive data available in literature. A nominal vane airfoil midspan profile is redesigned for minimum heat load by means of both design practice and two types of optimization algorithms. Resultsindicateanappreciablereductionintheoreticalheatloadrelativetotheoriginalvane;peakleading-edgeheat transfer was reduced and suction-surface transition onset was delayed significantly. A method for two-dimensional design optimization for aerodynamics and heat load is successfully demonstrated.

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