Study Of Synthesize Directional Cylinder Transducer Based On Longitudinal Vibration

In this dissertation researches are focus on synthesize directional cylinder transducerbased on longitudinal vibration. First of all, characteristics of the monopole, dipole, andquadrupole modes of synthesize directional cylinder transducer based on longitudinalvibration had been presented. Secondly, the theory and method for synthesized directionalbeam formation using monopole, dipole, and quadrupole modes had been described. Thenmodal analyses and harmonic analyses of transducer had been performed by using finiteelement analysis software. The influence of the performance of the transducer is different withthe parameter of the structure. The relationships had been studied. Finally, a prototype basedon the analysis of the optimization results and the actual situation had been made andmeasured.Test results show that the resonant frequencies are7.2kHz,10.6kHz and7.0kHz for themonopole, dipole and quadrupole modes respectively; corresponding to the maximumtransmitting voltage response are138.5dB,140.3dB and139.5dB. Transducer can form acardioid beam pattern when monopole, dipole, quadrupole modes weightings1:1:0; and forma super-cardioid beam pattern when monopole, dipole, quadrupole modes weightings1:2:1.Moreover when transducer operated in1000mode, not only directional emission can berealized, but also a wide operation bandwidth from6.8kHz to13kHz which the TVR with upsand down is less than3dB; and from6.4kHz to14.4kHz the TVR with ups and downs is lessthan6dB.