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Review: Active Control of Shock-associated Unsteady Flow Phenomena in Aeroengines - Suppression Techniques for Transonic Cascade Flutter and Supersonic Jet Noise -

Watanabe, Toshinori

SFB 1029 - TurbIn

Active control techniques for cascade flutter suppression and supersonic jet noise reduction were studied in the University of Tokyo. For flutter suppression, piezoelectric devices were installed on the blade surfaces. The active oscillation of the trailing edge of a blade was found to suppress the flutter instability in the numerical analysis. The effect was qualitatively confirmed in a trial experiment. For jet noise reduction, the technique of microjet injection was experimentally studied. The microjet could provide quite effective reduction of shock associated noise through the suppression of jet oscillation. The present paper briefly intro-duces these studies.