Vibrational Property Investigation in Longitudinal Magnetically-Tuned Piezoelectric Ultrasonic Composite Transducers

This research introduces an innovative composite piezoelectric ultrasonic transducer with magnetron tuning, enabling dynamic frequency modulation. The proposed configuration integrates three key components: a longitudinal sandwich-type piezoelectric transducer, a magnetically tuned resonance horn assembly, and a conical horn. An electromechanical equivalent circuit model was established to analyze the transducer's vibration characteristics. Theoretical analysis, finite element simulation using COMSOL, and experimental validation were conducted to evaluate the resonance frequency and vibrational modes under different conditions. The transducer incorporates Terfenol-D, a smart magnetostrictive material exhibiting variable Young's modulus characteristics under externally applied DC magnetic fields through the ΔE-effect. This magneto-elastic coupling mechanism facilitates precise electromechanical resonance adjustment, achieving real-time frequency modulation within the composite transducer system. Experimental results demonstrate that the transducer achieves adjustable resonance frequencies in real-time, making it suitable for applications such as pesticide spraying, fertilizing, irrigation, fuel atomization, wet desulfurization, dust suppression and atomized drug delivery. This research provides a foundation for the development of advanced ultrasonic transducers with tunable frequencies for diverse industrial and environmental applications.