Aeroelastic instability analysis of a turbomachinery cascade with magnetorheological elastomer based adaptive blades

摘要

Torsional aeroelastic analysis of a turbomachinery cascade comprised of three-layered sandwich blades embedded with Magnetorheological Elastomer (MRE) core layer is carried out in this paper. The MRE material is used as a constrained damping layer between two elastic skins in order to investigate its effects on the aeroelastic stability of a blade cascade. To formulate the structural dynamic of the blades, torsional theory of rectangular laminated plates is used and the unsteady Whitehead's aerodynamic theory is employed to model the aerodynamic loadings. Assumed modes method and the Lagrange's equations are used to derive the governing equations of motion of the coupled aeroelastic system. Then, the effects of different parameters on flutter stability of the blades cascade are studied in details. It is found that the magnetic field and MRE layer thickness have significant influences on the flutter boundary of the system and the mistuning of the magnetic field intensity has beneficial effect on the flutter stability. Additionally, the results confirm that the concept of sandwich blades provided with MRE core has capability to utilize as a passive treatment in turbomachinery applications for improving the flutter characteristics of the blades.