Potential of aeroelastic tailoring to improve flutter stability of turbomachinery compressor blades

Authors

Christoph Reiber - German Aerospace Center (DLR)
Michael Blocher - German Aerospace Center (DLR)

Abstract

To determine the potential of aeroelastic tailoring to improve flutter stability of carbon fiber turbomachinery compressor blades the structural dynamic and aeroelastic behavior of ten different laminate layups were compared. At first an operating point at off-design conditions was identified as flutter critical. Afterwards the dependency between laminate properties and eigenbehavior and between eigenbehavior and aerodynamic stability un-der these off-design conditions were described. The results show that for every of thefirst three natural oscillations certain conditions for the eigenmode and eigenfrequency have to be satified to evoke aerodynamically stable be-havior. Considering these constraints just one of the investigated laminates is suitable to ensure flutter stability for these certain flow conditions. This very small variety of applicable laminate layups shows the complexity to design aerodynamically stable compressor blades but also the great potential of aeroelastic tailoring to improve the flutter stability of carbon fiber turbomachinery compressor blades.