No abstract

No abstract

A planar array transducer consists of several transducers arranged on an acoustic window, which causes crosstalk. The crosstalk is a phenomenon in which the acoustic pressure generated by a projector is transferred to adjacent hydrophones through the acoustic window and the transferred pressure generates noise signals in the hydrophones. The performance of the planar array transducer is deteriorated due to this acoustic interaction, which should be minimized for maximum array performance. Analysis of the crosstalk has been carried out with sophisticated numerical methods, which motivated the need to develop a simpler and accurate analysis method. In this work, an equivalent circuit has been developed to analyze the crosstalk level of the planar array transducer, and the validity of the developed method has been verified by comparing the result from the equivalent circuit analysis with that from finite element analysis.

The structure of 1–3 piezocomposites has been optimized with such design variables as volume fraction of piezoceramics inside the composite and the thickness and aspect ratio of the piezoceramic pillars to enhance the performance of an underwater acoustic transducer operating in the thickness mode of the piezocomposites. Influence of the design variables on the transducer performance was analyzed with equivalent circuits and finite element method. In operation of the transducer, inter-pillar modes of vibration were likely to occur between piezoceramic pillars due to the lattice-structure of the piezocomposite, which could deteriorate the performance of the transducer. The structure of the 1–3 piezocomposite plate has been optimized to maximize transmitting, receiving and transmitting–receiving performance of the underwater acoustic transducer while preventing the coupling of the thickness mode with inter-pillar modes within the frequency range of interest. As results, volume fraction (VF) of 40.5% and aspect ratio (AR) of 0.4 showed the highest transmitting performance while VF of 30.0% and AR of 0.5 showed the highest receiving performance. For the transmitting–receiving performance, VF of 43.7% and AR of 0.5 were the optimal. Genetic algorithm was used in the optimal design.

No abstract