Experimental modal analysis of a rotor with active composite blades

Abstract This paper presents a modal analysis of a rotor with three active composite blades performed by different methods. The rotor blades were made of glass–epoxy unidirectional laminate. Active Macro Fiber Composite (MFC) elements were adhered on each composite blades. The experiments were performed on a test stand installed at a Structures Dynamics Laboratory at the Lublin University of Technology. The rotor was fixed during the measurement. A laser vibrometer and LMS analyzer with modal hammer were used. The experimental natural frequencies and mode shapes of free vibrations were determined. The laser vibrometer was equipped with a generator and scanning heads with a video camera. In order to activate vibrations, MFC elements powered by a high-voltage amplifier were used. The experimental results were developed using PSP software. Next, the LMS analyzer with modal hammer was used as force and acceleration sensor. Finally, a numerical modal analysis was performed. The simulations were performed by the finite element method using the Abaqus software package. The numerical results and the experimental findings show a very good agreement. All results were compared with the results of modal analyses for the cantilever composite beam and the fixed rotor with one composite blade.