TUNABLE MAGNETOSTRICTIVE DYNAMIC VIBRATION ABSORBER

We present a tunable Magnetostrictive Dynamic Vibration Absorber (DVA) developed within the European project MESA to tackle the problem of vibration and noise in turboprop aircraft. The tunability of the apparent mechanical stiffness and damping coefficients of the DVA is achieved through the proper feedback of the force generated in the magnetostrictive rods to adapt the resonant frequency and damping of the passive DVA to the time-variant first blade pass frequency. Experimentally obtained vibration absorbing characteristics with and without hysteresis compensation are presented. The resonant frequency of the tunable DVA can be varied electronically by about 15%. Implementation of the hysteresis compensation improves the range and stability of DVA tuning.