Reliability Analysis Of Piezoelectric Structure

The intelligent structures, which comprise piezoelectric sensors and actuators, have important application in the fields of aeronautics and astronautics. Now the researches of piezoelectric structure are mainly vibration control and deformation control. The piezoelectric structural systems like many other structural systems contain many stochastic factors. For example, the loads which act on the structures, the trim size of the components, the elastic module of the structural material, and their breakdown strength are stochastic; so the reliability analysis of the piezoelectric structure is quite important. For the most part this thesis have done the static reliability analysis of the piezoelectric laminate, the static reliability analysis, stable reliability analysis, and the dynamic reliability analysis for the piezoelectric frame. The main content are as following.1. For the intelligent frame structures, the finite element models are established, they comprise static model, stable model and dynamic model. On the basis of those finite element modes, the static stable and dynamic reliability analysis of the piezoelectric frame are done.2. For the piezoelectric laminates, on the basis of the static finite element equation, the static reliability is analyzed under the mech-electric coupling effect.3. To research the failure mechanisms of the piezoelectric material. In the process of static and dynamic reliability analysis, according to the failure criterions of the piezoelectric actuator and sensor presented, safety margin functions of failure modes, which are caused by fracture damage or electrical breakdown, are established.4. Basing on the stochastic variables of material fracture stress, breakdown strength of electric field, inertia and area of the section, loads and external electric potential, Taylor expansion SFEM is adopted to get partial derivative of the safety margin function, as well as the reliability of the structure system, through which the reliability index of structure system is acquired.