The traditional approach in flutter calculations of cascade has been to apply frequency domain analysis. In this approach, the blade motions are assumed to be harmonic functions of time with a constant phase lag between adjacent blades. The equations of motion then reduce to an eigenvalue problem; the elgenvalues determine stability. This analysis is restricted to linear structural equations and aerodynamic forces that are linearly dependant on the displacements. The unsteady aerodynamic forces used in such an analysis are typically based on classical linearized potential theory, but allows the use of efficient semianalytical solution methods.
展开▼
