Numerical simulation of a piezoelectric loudspeaker including viscothermal effects for hearing aid applications

摘要

Piezoelectric materials are already widely used in applications involving miniaturized components. The application of these materials in hearing aid receivers may present technical and economic advantages such as reducing the number of parts of the system and its manufacturing cost. The vibro-acoustic analysis of a piezoelectric component involves the construction of multi-physical models. Analytical models of piezoelectric components can be found in the literature, but these models involve in general very simple geometries or are very simplified. This work presents a multi-physical numerical model of a miniaturized speaker prototype. The numerical model was constructed using the Finite Element Method (FEM). This speaker is composed of a piezoelectric diaphragm coupled to a small cavity. The multi-physical model is composed of piezoelectric, structural and acoustic coupled FEM model. The acoustic model of the small cavity also accounts for thermal and viscous effects on the acoustic propagation. Finally, the multi-physical model is experimentally validated.