Vibro-acoustic design, manufacturing and characterization of a tonpilz -type underwater acoustic device

Sonar is an electro-acoustic system that can detect an object and give information about the location of this object with the help of sound waves. The most important parts of sonar systems are transducers which are in contact with water and produce and receive sound waves. Tonpilz-type transducer is one of the most popular type of transducers used in underwater-acoustics. It is used generally for low frequency applications. This thesis covers designing, manufacturing and performing underwater acoustic tests of Tonpilz-type transducers operated below 7 kHz. Firstly, transducers are designed according to the technical specifications. Design of the transducers consists of three steps as simple lumped parameter method, equivalent circuit method and finite element method, respectively. Three transducers are specified at the end of the design process by considering the predefined specifications and then they are manufactured. Characterization and underwater acoustic tests of the transducers are performed at acoustic measurement facilities of the Meteksan Defense Industry Inc. (Ankara). When the results from the measurements are compared with the results from the design stages, it is seen that the results are matched well to each other. Maximum TVR values are found as 132.3 dB at 4.7 kHz, 133.7 dB at 4.9 kHz and 137.3 dB at 4.7 kHz for the three different manufactured transducers. Maximum RVS values are found as -154.7 dB at 4.7 kHz, -159.1 dB at 4.9 kHz and -156.8 dB at 5 kHz. As a result, three low-frequency transducers having sufficient acoustic performances have been successfully designed and manufactured.