PASSIVE VIBRATION SUPPRESSION OF STRUCTURES IN THE VICINITY OF NATURAL FREQUENCIES USING PIEZOEFFECT

Abstract

The proposed method of passive vibration suppression of structures is based on the use of the piezoe­lectric effect, which consists in the ability of the piezoelectric material to convert electrical energy into mechani­cal energy, and conversely. As it is known if the frequency of forced vibrations tends to the resonant frequency, all the desired quantities (forcers, moments, displacements and deformations) grow indefinitely. A new idea is that as we approach the resonant frequency, we change the electrical conditions on the electrodes of piezoelectric layers, thereby obtaining a different boundary value problem and a different spectrum of natural frequencies. Thus, we manage to get away from the resonant vibrations of the structure. Using the example of a laminated beam with elastic and piezoelectric layers the possibility of damping vibrations caused by mechanical load is studied. In this paper, a mathematically based model is used to solve the problem in question. The calculations are performed and the results are presented in the form of graphs. It is shown that forcers, moments, displace­ments and deformations of beam in the vicinity of the natural frequency can be significantly reduced by as a re­sult of changes in the electrical conditions on the electrodes of the piezoelectric layers.