EXPERIMENTAL-STUDY ON VIBRATION OF A ROTATING BLADE

The vibration of a rotating blade is investigated in this work. A roto r system is built and natural frequencies of the rotating blade are me asured and compared with the numerical results from a finite element a nalysis. The experimental setup has a strain-gage-based telemetry syst em and a piezoelectric shaker that rotates with the rotor. The finite element model of the beam is derived based on the Timoshenko beam theo ry. The effects of varying rotating speeds and stagger angles on the b lade natural frequencies are studied. The results indicate that the na tural frequencies calculated from the finite element model and the exp erimental values are in good agreement. It is found that the blade nat ural frequencies increase with the rotating speed in a nonlinear way. The effects of the stagger angle on the measured natural frequencies a re not clear.