Determination of piezoelectric transducers damping by using experimental and finite element simulations

The study of piezoceramic and piezoelectric transducers behavior by finite element method (FEM) shows an important influence of viscous damping. Damping values for piezoceramic materials are not provided by manufacturers. In addition, damping values for non-piezoelectrics materials, such as, resins, steel, aluminum, etc, which are usually applied to assemble these transducers are not appropriately given for FEM simulations. Therefore, the objective of this work is to determine damping values of these materials so they can be used in a FEM software, such as, ANSYS, which has four different ways for damping input. Damping values are determined by combining experimental and numerical techniques. For piezoceramics the damping is determined through the quality factor (Qm) by measuring the admittance curve which are influenced by damping. By using these damping values, harmonic and transient FEM simulations of piezoceramics and piezoelectric transducers are performed and the simulated admittance curve is compared with the measured one, as well as, displacement results are compared with laser interferometer measurements. Damping determination for non-piezoelectric materials are done by comparing experimental and simulated displacement and electrical admittance results. By using the obtained damping values, experimental measurements and simulated results for different piezoelectric transducers show a very good agreement.