| Development in the field of projector design is spurred on mainly by three motivating forces: the extensive research in underwater propagation establishes the advantages of increasing lower frequencies for long range detection, the advent of new active and structural materials leads to substantial improvements in transducer performance , applications of the computer technology. The low-frequency and high-power projector have became the primary candidate of sonar system application since the early 1980s.Among them, the flextensional transducers are the low-frequency and high-power projector applied the most widely and the most ideally. But the biggest disadvantage of flextensional transducer is the complicated design, has obstructed the development of flextensional transducer. Recent years, accompaning with the development of computer technology it has a trend which using the finite element method(FEM) to design transducers. This paper presents the design of outboard-driven flextensional transducer using FEM software ANSYS.This paper discussed the trends and problems in low-frequency and high-power transducers design and gave out the solutions based on review the development status in recent years. We deduced the basic theoretical formula for analyse piezoelectrics and acoustic fluid using FEM. Subsequently, we presented the brief introduction of finite element analysis software ANSYS and the applied method of designing transducers.In the part of thesis's design, we calculated the frequency characteristics,radiation characeristics and resistance characteristics of outboard-driven flextensional transducer, and optimized the size of structure. We pointed out that the resistance was the chief problem encountered in outboard-driven flextional transducer design.According to the results of optimizing design,we carried out the static stress analysis and the dynamic stress analysis, and insured the safety of the later assemble processes. We calculated the electro-acoustical characteristics of designed transducer using the postprocess functions of ANSYS.According to the above work, we manufactured and measured the real outboard-driven flextensional transducer ,then comparing with calculating result. Finally ,we summarized the problems which have leaved behind and the work directions in the future. |
