A Near-Field Acoustic Holography-Based Sound Isolation Measurement Method Resistant to Flanking Transmission

Sound insulation measurement based on near-field acoustic holography utilizes near-field acoustic holography to reconstruct the surface sound pressure of building components. However, accurate reconstruction of acoustic parameters is hindered in the presence of flanking transmission on the holographic plane. This study presents a high-order method for separating the external sound by formulating a seismic model (WRW model) in wavenumber-space. Unlike previous studies, this method does not require the measurement of multiple holographic acoustic data or multiple types of acoustic data on the same holographic plane. It relies solely on single holographic plane sound pressure data to achieve high-precision restoration results. The numerical simulation results show that at frequencies below 1500Hz, the reconstruction error of using the Morozov difference principle to select regularization parameters is about 9%. Compared with the planear near-field acoustic holography method for reconstruction, the reconstruction error is reduced by about 24%. When the steady state noise disturbance reaches 10% of the maximum value of the holographic sound pressure, the reconstruction error within the above frequency band still remains at 9%, indicating that the reconstruction results are less affected by noise interference. Experiments verify the effectiveness of the algorithm in the low frequency range. This method can significantly increase the robustness of sound field reconstruction, providing theoretical support for sound insulation measurement under flanking transmission interference.