Numerical analyses of flutter characteristics of titanium and composite fan rotor blade

摘要

The flutter characteristics of composite fan rotor blades are compared with those of titanium blades by computational fluid dynamics (CFD). The structural characteristics of the fan blade, used for flutter analyses, are analyzed by Finite Element Method (FEM) . The computational results revealed that the unsteady aerodynamic work induced by shock wave on suction surface is dominant for vibration instability both of titanium and composite rotor blades in transonic flow condition. Composite fan blade is more stable than titanium fan blade concerning cascade flutter because natural frequency of composite fan blade is higher than that of titanium fan blade. But mode shape of titanium blade is more stable than of composite fan blade if natural frequency is same in the present fan model.