Development of advanced compressor airfoils for heavy-duty gas turbines

The development and experimental validation of a new family of subsonic compressor airfoils for use in heavy-duty gas turbines is presented. The new profiles are characterized by low losses and wide operating ranges. In particular the influence of the higher airfoil Reynolds numbers compared to aeroengine compressors and the impact of these differences on the location of transition are taken into account. The design process itself is carried out by the combination of a geometrical code for the airfoil description with a blade-to-blade solver and a numerical optimization algorithm. The optimization process includes the design-point losses for a specified Q3D flow problem and the off-design performance for the entire operating range. The superior performance of the new airfoil family is demonstrated by a comparison with conventional controlled diffusion airfoils (CDA). The advantage in performance has been confirmed by detailed experimental investigations of six profiles in the DLR transonic cascade tunnel.