Development of a contact layer in the finite element model of ultrasonic transducers to evaluate losses in contact surfaces

Abstract

In this research, a 3D finite element model of an ultrasonic transducer has been developed, considering the losses between components. These losses are modeled by defining viscous dampers at interfaces. The friction between components is evaluated using the BKE contact mechanics model. The results show that the friction losses do not significantly reduce the vibration amplitude. However, due to the mismatch of acoustic impedances, the reflection of acoustic waves in the interfaces of components causes many power losses. By applying the equivalent damping, the error of the amplitude of the vibrations was reduced to 2.56%. In contrast, this error was very high in previous articles. The resonance and anti-resonance frequency errors are 2.63 and 0.86%, respectively.