Influence of neighboring blade rows on the unsteady aerodynamic response of cascades
An analysis of the unsteady aerodynamic response of cascade due to incident gusts or blade vibration when the cascade is part of a multistage fan, compressor, or turbine is presented. Since most of the current unsteady aerodynamic models assume the cascade to be isolated thereby neglecting the important influence of neighboring blade rows, an elegant and computationally efficient method to model the neighboring blade row effects is also presented. Numerical results are shown for both the gust response and blade vibration problems. To validate the model, the results are compared to other analytical models, and to a multistage vortex lattice model. It is shown that the effect of neighboring blade rows on the aerodynamic damping of vibrating cascades is significant, but can be modeled with a small number of modes.