Using Anti-acoustic Baffle Design to Realize the Directivity of Transducers and Arrays

Directivity is not only one of the important performance in dicators of the transducer, but also determines the spatial characteristics of the acoustic system. The conventional directional angle and side lobe level parameters can be calculated by theoretical formulas. However, the vibration characteristics of the radiation surface of the transducer, the coupling between the elements and the characteristics of the baffle also have great influence on the directivity, especially the influence of the baffle, which makes the directivity of the transducer very complex and the opening angle difficult to be controlled. Studying the influence of baffle on the directivity of the transducer, using the reflection of the baffle reasonably to improve the directivity of the transducer, so that the directivity angle meets the design requirements, is a scientific problem often encountered in engineering and needs to be solved. This paper uses anti-acoustic baffles to improve the design and achieve the directivity of several commonly used underwater acoustic transducers and base arrays, including spherical transducers, cylindrical transducers, longitudinal vibration transducers, and linear array elements. By using the virtual source method, through theoretical derivation and finite element simulation, the factors affecting the directivity of the transducer under the action of the anti-sound baffle are analyzed. Theoretical calculation, simulation analysis and experimental verification show that the working frequency of the transducer or element, the distance between the sound center and the baffle, and the size of the baffle are the important factors affecting the directivity of the transducer.The paper obtains half-space radiation transducer, low axial beam cylindrical transducer, wide beam longitudinal vibration transducer and wide beam elementary line array by adjusting various influencing factors. The improvement measures obtained in this thesis have important guiding significance in the application of acoustic system or transducer engineering.