This paper describes the methodology and limitations found in the design and development of piezoelectric transducers for applications in fluids by finite elements method (FEM). In these linear models for the acoustic-structure interaction approximate numerical solutions have been obtained. In order to perform the calculations, simplifications only valid for low-power sound waves propagating in incompressible, irrotational and inviscid fluids have been assumed.
When different physical systems interact with each other, the solution of one of them cannot be obtained independently without the simultaneous solution of the other, since the forces acting at the interfaces are unknown. These systems are known as coupled systems. Numerical modelling of piezoelectric transducers implies coupling the physics associated with piezoelectric elements, structural elements and fluid elements (with different degrees of freedom), resulting in complex models with difficult convergence. The selection of appropriate mesh refinement, boundary conditions and configuration parameters of the calculation methods is of great importance to obtain the numerical result.
