FORCED VIBRATIONS OF METAL-PIEZOCERAMIC THIN COMPOSITE CIRCULAR PLATE EXCITED WITH HOMOGENEOUS PRESSURE

In this paper, forced vibrations of general metal-piezoceramic thin composite circular plate, excited with uniform pressure. are discussed under open-circuit electrical boundary condition. The general thin composite circular plate are constructed using two piezoceramic disks of radius b and one thin metal circular plate of radius a. The general thin composite circular plate can be simplified to the various special thin composite circular plate and the homogeneous elasticity thin circular plate. After correctly arranged polarity of piezoelectric ceramics, flexu-ral vibrations of the system can be excited with uniform pressure, and so the open-circuit voltage is obtained at electrical terminal.
The equations of motion, continuous conditions and boundary conditions of the system are derived from Hamilton's principle. The exact solutions and the equations of resonant frequency for simply supported edge and clamped edge are obtained. The resonant frequencies, obtained from this equations of frequency, are the parallel resonant frequencies of the electrical impedance. Under the clamped boundary condition, the equation of resonant frequency of the special thin composite circular plate for b=a ate similar to those of homogeneous thin circular plate, only their parameters are difference. The exact solution and the equation of frequency for simply supported edge are also obtained.
For the convenience of the engineering, the approximate solution of forced vibration, excited with uniform pressure, and the equation of resonant frequency of general thin composite circular plate are obtained with Rayleigh-Ritz method. The effective electromechanical coupling factor is also shown. The approximate resonant fresuencies and the effective electro mechanical coupling factor are in good agreement with the experiments.