Design optimisation of circular piezoelectric bimorph actuators using finite element analysis

In this work, finite element simulation is used to optimise a circular piezoelectric bimorph bender actuator. The piezoelectric bender actuator consists of a circular base membrane with a circular piezoelectric bimorph bonded to one side of the base membrane by epoxy glue. Many parameters have been considered during preliminary design, in which the oscillating membrane thickness, lead-zirconate titanate (PZT) thickness, input voltage and frequency play a vital role. The piezoelectric plate will oscillate the membrane during alternating voltage is applied towards the piezoelectric plate. Once the pulse voltage is applied to the piezoelectric plate, convex/concave deformation will occur on the structure. To obtain extreme deflection of the actuator, it is imperative that thickness ratio of bimorph to the base plate is optimised. Keeping the base plate diameter and the thickness constant, a parametric analysis is performed to find the bimorph diameter and its thickness for maximum deflection. The piezoelectric sheet thickness is chosen by iterating various thickness of the piezoelectric plate to actuate the membrane. The numerical simulation results show that for certain Aluminium membrane thickness, there will be an optimal coupling thickness of the piezoelectric plate. Transient analysis of this membrane is obtained by changing the voltage (200V, 0V, -200V, 0V) alternatively in equal intervals of time. Copyright © 2021 Inderscience Enterprises Ltd.