High Power Ultrasonic Radiator in Liquid

Abstract

In this paper,anew type of high power ultrasonic radiator used in liquid is studied. The proposed ultrasonic radiator is ametal cylinder with comparative radial and longitudinal geometrical dimensions, which is mechanically excited by al ongitudinal sandwich ultrasonic transducer.T he physical mechanism of the high power cylinder radiator lies in the intense coupled vibration between the longitudinal and radial vibrations of the cylinder with large geometrical dimensions. The equivalent circuit for the coupled vibration of the cylinder radiator is derived, and the resonance frequencyequations are obtained. The coupled vibrational modes of the radiator are analyzed and the optimum condition for the intense simultaneous resonance of the longitudinal and radial vibrations is acquired. The resonance frequency, the admittance-frequencycurve, the vibrational displacement distribution and the radiated acoustic field are numerically simulated and experimentally measured. It is experimentally shown that the measured results are in agreement with the analytical and numerical results, and the cylinder radiator with large geometrical dimensions can be excited into both longitudinal and radial vibration. By properly choosing its geometrical dimension, the cylinder radiator can be designed to resonate at longitudinal and radial vibration simultaneously.T herefore, it is expected to be used as high power ultrasonic radiators in ultrasonic cleaning, ultrasonic processing and ultrasonic sonochemistry. PACS no. 4335.-c, 43.38.-p 544 ©S.Hirzel Verlag · EAA Lin et al.:H igh power ultrasonic radiator ACTA ACUSTICA UNITED WITH ACUSTICA Vol. 97 (2011)

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