Unsteady Swirling Flows in Annular Cascades, Part 2: Aerodynamic Blade Response

A model is developed for the interaction of unsteady incident disturbance in a swirling mean motion with an annular cascade of unloaded blades. The incident disturbances are modeled by using a combined eigenmode analysis with initial-value problem solutions as described elsewhere (Golubev, V. V., and Atassi, H. M., “ Unsteady Swirling Flows in Annular Cascades, Part 1: Evolution of Incident Disturbances,” AIAA Journal, Vol. 38, No. 7, 2000, pp. 1142 ‐1149). The scattered e eld is calculated in response to the blade upwash and accounts for the effects of the centrifugal and Coriolis forces induced by the mean swirl. Benchmark resultsarepresented fortheunsteady blade pressure in the rotor-wake/stator interaction problem. These results are compared with the strip theory and show strong dependence on the swirl-induced changes in the radial distribution and axial evolution of the incident vortical disturbances.

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