The aeroelastic stabilities of 2-D cascade are investigated. The steady and unsteady aerodynamic forces are computed by using a 2nd-order total variational diminishing, time-marching and finite volume Euler code. The unsteady aerodynamic forces are computed by using the methods, such as the stacked boundary condition, the Fourier periodic boundary condition and the influence coefficient technique, and are compared with one another considering interblade phase angles.
Aeroelastic analyses for a typical section having pitching and plunging motions are performed in frequency domain. The effects of interblade phase angle and reduced frequency on the aeroelastic stability are investigated. The unsteady aerodynamic forces computed by three methods coincide very well. Interblade phase angle affects the unsteady aerodynamic forces and aeroelastic stability considerably. When the offset between the elastic axis and the mass center is zero, the most unstable interblade phase angle for flutter exists around 90 degrees and the flutter mode is the pitching mode. When investigating the effect of interblade phase angle on flutter, the influence coefficient technique is most efficient in view of computational time.
