Use of single crystal and soft piezoceramics for alleviation of flow separation inducedvibration in a smart helicopter rotor

Abstract

Dynamic stall and flow separation induced vibration alleviation is investigated using singlecrystal and soft piezoceramic-induced shear actuation. PZT-5H performs well to reducevibration at cruise speed (about 50%) but fails to achieve a substantial vibration reduction(about 20%) at high speed forward flight because dynamic stall and flow separation requirea larger stroke for vibration reduction. -induced shear actuation is found to generate a larger stroke and eventually a highervibration reduction (about 60–70%) at both cruise and high speed flight. It is observed thatthe controller performs satisfactorily up to a noise level of 20% in the sensed data.Optimum placement of actuators along the span, as well as the eventualities of actuatorfailure and degradation are also addressed.