Study on Recovering the Free and Far field Radiation Acoustic Characteristics of An Underwater Box

It is very important to acquire the free-field acoustic characteristics of targets for noise control. To reduce requirements for test environments, a method combining sound field recovery technique based on boundary element method (BEM) and supersonic sound intensity technique is proposed. According to the numerical simulations, the acoustic characteristics of targets such as the sound pressures and sound powers can be recovered by sound field recovery technique based on BEM in a noisy bounded environments. At the same time, supersonic sound intensity technique is used to filter out evanescent waves and identify the hotspots of far-field acoustic radiation in near field. The proposed method can be used to acquire the free-field acoustic characteristic of the target and identify the hotspots radiating to the far field in a bounded, noisy and near field. This method breaks through the limitations of test environment and has engineering application value.