The study of the spatiotemporal characterization of wall-pressure fluctuation on a skin made of micro floating raft arrays based on wavenumber frequency spectra

Abstract Controlling hydrodynamic noise in underwater vehicles is critical, with wall-pressure fluctuations being a key source. Exploring the spatiotemporal characteristics of these fluctuations is vital for hydrodynamic noise evaluation and control. This study investigates the spatiotemporal characteristics of wall-pressure fluctuations on a novel Micro-Floating Raft Array System (MFRAS) skin using wavenumber-frequency spectrum analysis. A fluid-structure interaction (FSI) model base on large eddy simulation (LES) is used to calculate the wavenumber-frequency spectra. Comparing the wavenumber-frequency spectra of MFRAS against those of the flexible skin and the bare wall, it is found that the MFRAS can promote the fragmentation of large eddies into small eddies and dissipate turbulent kinetic energy (TKE). Across inlet velocities of 5–11 m s −1 , the maximum spectral levels of the wavenumber-frequency spectra of the MFRAS are 7–10 dB lower than the bare wall and consistently 1 dB lower than the flexible surface. The influence of the key MFRAS structural parameters on the wall-pressure fluctuations is also be studied. A smaller distribution spacing without interference is beneficial for improving the TKE dissipation performance of MFRAS; Young’s modulus affects the elastic deformation of MFRAS, and excessively small or large elastic deformation is detrimental to the TKE dissipation performance of MFRAS; middle mass height affects TKE dissipation by regulating the system’s natural frequency, which should be chosen due to specific wavenumbers and frequencies that requires control.