Abstract: Based on the longitudinal composite piezoelectric ultrasonic transducer, the radial vibration characteristics of composite pipe power ultrasonic transducer with pre-stressed metal pipe shell are studied. The radial composite pipe ultrasonic transducer consists of a short piezoelectric ceramic pipe and a short metal pre-stressed pipe shell. Based on the electromechanical analogy, the equivalent circuit of the radial composite transducer is set up and the resonance frequency equation is derived. The relationships among the resonance frequency, the anti-resonance frequency, the effective electromechanical coupling coefficient and the radius ratio of pre-stressed pipe are analyzed and discussed. By testing the resonance and anti-resonance frequencies of four samples of radial composite pipe piezoelectric ultrasonic transducer, it is shown that the theoretical resonance frequencies agree well with the measured results and the errors are less than 5%.

Key words: Antiresonance frequency, Frequency equation, Pipe piezoelectric ultrasonic transducer, Radial vibration, Resonance frequency