An Underwater Non-free Field Sound Radiation Prediction Technology Based on Sound Field Separation

Traditional measurement techniques have limitations in the low-frequency range of underwater non-free field. In this paper, a sound field separation measurement technique based on “Supersonic Intensity in Reverberant Environments“ (SIRE) is adopted, which separates the outward and inward waves of the underwater sound source in unknown field conditions, and filters out the evanescent waves and calculates the radiated sound power. The radiated sound power of pulsating spherical source in an underwater non-free field is numerically calculated by the finite element method (FEM), and the accuracy of the algorithm is verified by comparison with the analytical solution. The prediction of the radiated sound power of the elastic cylindrical shell in the low-frequency range in the underwater non-free field is realized, and the influence of the measuring radius of the holographic surface and the measuring points on the measuring accuracy is analyzed. The results show that this technique is accurate in calculating the radiated sound power of underwater sound source in the low-frequency range of non-free field, and provides necessary conditions for vibration reduction and noise reduction of the underwater sound source.