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Performance Comparison between Piezoelectric and Elastomeric Lag Dampers on Ground Resonance Stability of Helicopter

In this study, a piezoelectric lag damper using damping characteristics in piezoelectric ceramics is proposed to alleviate ground resonance instability. The piezoelectric passive damper consists of piezoelectric elements and electrical circuits such as resistors and inductors in a series. By bonding the piezoelectric ceramics to the rotor flexures, piezoelectric strain energy is converted to electrical energy and dissipated through an electrical network. To verify the effect of the piezoelectric damper on rotating blades, experiments for the aeroelastic stability of the rotor blades were carried out. The experiment results for rotor blades with the piezoelectric damper show that the piezoelectric damper has a strong stabilizing effect on the inherently weakly lag-mode damping of the blades. The performance of piezoelectric and elastomeric lag dampers on ground resonance instability are compared and modal frequency and modal damping with respect to rotating speed are shown.