Summary: | 碩士 === 清雲科技大學 === 機械工程研究所 === 98 === This thesis investigates the transverse vibration characteristics of piezoceramic composite plates under different boundary conditions by applying the electroelasticity and Kirchhoff plate theory. By comparing the characteristic equations of resonant frequencies between isotropic and piezoceramic-metal composite disks, the named equivalent Poisson’s ratio and bending stiffness are derived, and then the transverse vibration characteristic equation can be expressed as single formulation. The numerical calculations obtained by finite element method (FEM) and a optical technique, amplitude-fluctuation electronic speckle pattern interferometry (AF-ESPI), are also employed to validate the theoretical analysis. It is shown that the theoretical predictions, including the resonant frequencies and mode shapes, agree rather well with numerical results and experimental measurement. Through means of the concept of equivalent constants, the resonant frequencies and mode shapes of annuli under different boundary conditions are also obtained. According to the theoretical calculation, the variations in resonant frequencies versus the various layer-thickness ratios for annuli with different boundary conditions are investigated in the thesis.
|