Journal of the American Ceramic Society, Vol.90, No.3, 850-857, 2007
Finite element modeling of a donut flextensional transducer
A new flextensional transducer based on the cymbal device was designed and fabricated. The endcap shape of this device, called the donut, was developed through finite element modeling using the commercially available software code ATILA((R)). Endcap dimensions that were studied in this research include cap thickness, flange width, and cavity depth. Other parameters considered included piezoelectric material type, thickness of the piezoelectric disk, epoxy thickness, and endcap metal. Fundamental flextensional resonance frequency and effective coupling coefficient, which are two important characteristics that determine the performance and the application opportunities of the transducer, were predicted. Finite element analysis coupled with experimental results suggest that these devices have higher flextensional resonance frequencies compared with cymbals of similar dimensions. Impedance spectroscopy of the donut devices also suggests that the effective electromechanical coupling coefficient is higher than cymbal devices of similar dimensions.