A barrel-stave projector with active material shell

A new barrel-stave transducer with special active shell made by giant magnetostrictive material Fe-Ga alloy called Galfenol is presented. Finite element analysis is carried out to simulate the magnetic fields and electroacoustic performance of them at first. It is shown that the projector with active shell could achieve better performance. Then two prototype transducers with the same volume and weight are fabricated and measured. The maximum transmitting current response is 168.4dB at the resonant frequency of 1750Hz for the one with Galfenol shell, and its maximum source level reaches to 180.1dB. In comparison, the maximum transmitting current response is 163.6dB at 1900Hz, and the maximum source level is 175.3dB for another with aluminum shell. It is confirmed that the barrel-stave transducer with active material shell has lower working frequency and higher sound power under the same conditions.