An Approach to Designing a Dual Frequency Piezoelectric Ultrasonic Transducer

This paper has been devoted to such approach for designed and fabricated the dual frequency piezoelectric ultrasonic transducer having longitudinal vibrations for high power application. By using analytical analysis, the resonance frequency equations of the transducer in the half-wave and the all-wave vibrational modes were determined for the assumed first resonance frequency of 25kHz. According to the resonance frequency equation, four transducers with two different constructions (Type A and B) were designed and made. The finite element method provided by commercial ANSYS was employed for FEM modeling and analysis of the transducer to observe its vibration behavior. It was shown that there is a good agreement between the experimental and FEM results. The designed and fabricated transducer can be excited to vibrate at two resonance frequencies, which correspond to the half-wave and the all-wave vibrational modes of the transducer, and use of Type B transducer greatly increased the mechanical quality factor (Q) of piezoelectric transducers.