Aeroelastic investigation of an open 3D steam turbine test case and blade shape optimization with improved flutter behavior

The paper describes the flutter stability assessment of a steam turbine rotor and application multi-disciplinary shape optimization procedure to obtain new flutter-free profile. investigated test case consists last stage representative modern industrial blading, firstly presented by Durham University intensively during years. aerodamping results original geometry, obtained non-linear method, are compared with those already published other researches different approaches (linearized, harmonic balance, non-linear). present in complete agreement numerical investigations literature show high instability for first bending mode. Starting from this unstable an aeromechanical has been applied order stabilize row while maintaining similar aerodynamic performances constraints. optimum profile shows relevant improvements terms stability, which exhaustively discussed geometry.