Study On Piezoelectric Accelerometers Fe Model And Its Application

On the basis of full investigation on R & D status of piezoelectric accelerometer, thefinite element models of the typical structure of the piezoelectric accelerometer isestablished. Through simulation and experimental research, it shows that finite elementsimulation is valid and effective in piezoelectric sensor.The piezoelectric element of an accelerometers converts the stress generated byvibration into charge output. The Generally piezoelectric accelerometers have beenusing analytical model to research the single degrees of freedom spring-mass system. Thecoefficient of elasticity of the piezoelectric material and positive piezoelectric effectparameters to evaluate piezoelectric accelerometer sensitivity and frequency responsecharacteristics. The analytical and combined analytical-experimental methods are used todesign piezoelectric accelerometer and modify its specification.The finite element method(FEM) is an efficient, accuracy and economical method forstructure design. Based on the theory of elastic mechanics and variational andinterpolation principle , the contiguous region in the real model can be discretized intogroups of finite elements using technique, The FE analysis for the coupled field problem ismore sophisticated. FEM have become a new practical numerical simulation in the field ofacoustics and smart structure research.Forward electromechanical coupling piezoelectricity finite element model wasproposed to simulate the performance of piezoelectricity accelerometer and then FEM forpiezoelectric accelerometer is constructed. Modeling procedure and the calculationmethod is given in accordance with the finite element simulation software ANSYS, andexploratory study is making to the finite element analysis method which applys to thesimulation of technical indicators in the piezoelectric accelerometer. Compare numericalsimulation results with the measured data indicate that verify the practicality andeffectiveness of the finite element model of the piezoelectric accelerometer.Simulative and experimental research is accomplished for Delta shear mode,compressive mode and planar shear mode accelerometer respectively. The numerical simulation result and calibration data is compared and study. Good agreement is achievedbetween simulated results and calibration. It is proved that the FE modeling can beeffectively used to predict the specifications of the accelerometer. Especilly to evaluateand anlysis the frequency characteristics of piezoelectric accelerometer, its numericalresult can reach the exact level, the all simulation error is less than 10%.Simulative study of typical sensor structure and metal material property, piezoelectricparameter is made in the dissertation. The resonance modes, stresses and chargedistributing of piezoelectric structures are analysed. The FE model can give the results ofqualitative and quantitative analysis for the specification of the accelerometer.Accurate finite element computer model provides a powerful assistant for traditionalmethods. The finite element method gives more accurate forecasts to the designperformance of the piezoelectric accelerometers, and more detailed simulation tospecification, the simulation results are visualized entirely. It is proved that the FEM canbe effectively used to resolve the problem of electromechanical coupling field.The FEdeveloping technology forms the bases of fast responsiveness and flexible design ofpiezoelectric accelerometers. This study has great practical value to the piezoelectricaccelerometer design and the optimization specification.