Research on the reverberation measuring technique of underwater directional sound sources

Abstract

The radiated noise of underwater directional sound sources was generally measured in the corresponding ocean environmental condition. Influenced by the ocean environmental noise, the reflection of ocean bottom and ocean surface, it is very difficult to get the radiated sound power of underwater directional sound sources. Reverberation method used in the Architectural acoustics was taken in this paper for measuring the radiated sound power of underwater directional sound sources. It has been used in the radiated sound power measurement of underwater spherical sound sources, but never been used in underwater directional sound sources. The reverberant theoretical formula of directional sound sources was derived by introducing the directivity factor. The radiated sound power of directional sound sources such as dipole and the two same-phase sphere was measured. The measuring and analyzing results show that the reverberant radius of directional sound sources is related to directivity factor. With the directivity factor turns strong, the reverberant radius will become larger but the reverberant controlled area will become smaller, so the measurement range of spatial averaging will become small. The radiated sound power of directional sound sources such as dipole and two same-phase spheres can be measured by large-range of spatial averaging. The measurement techniques can apply to measure the radiated sound power of underwater complex sound sources.