Finite Element Analysis For Structural Dynamics And Active Control Of Piezothermoelastic Plates And Shells

An eight-node solid-shell element, an electric potential element with nonlineardistributed and an isoparametric thermal element have been used to establish the coupledthermo-piezoelectric-mechanical element. The piezothermoelastic finite model of platesand shells is formulated based on the Hellinger-Reissner variational principle. Hybridstress and assumed natural strain (ANS) are adopted to immune to shear, membrane,trapezoidal, thickness lockings. According to the present finite model, the static anddynamic problems of overall and distributed piezoelectric sensor/actuator are calculated toobtain the influence of external load, electric and temperature field to mechanical behaviorsuch as deformation, mode and active control. The numerical results show that the presentmodel is effective and accurate. The effect of environmental factors such as electric,thermal load on the static and dynamic performance of overall and distributed piezoelectricstructure can be validated by the related examples in which thermal load only effectsmechanical load and electric load effects both mechanical load and stiffness with presenthypothesis.Then according to the linear finite model, the finite model for the active control ofpiezoelectric and piezothermoelastic system is presented by the method of negativevelocity feedback. Further, modified feedback control method is provided in order toeliminate the gap caused by thermal load.Finally, nonlinear piezothermoelastic finite model is established using incrementalmethod when geometric non-linear is considered. The influence of geometric non-linear isstudied and the result shows that the nonlinear model is more accurate.