Investigation of the effect of adaptive characteristics on non-cavitating noise for flexible propeller in non-uniform flow via the fluid-structure interaction model

When constructing a low-noise submarine, it is crucial to consider the non-cavitating noise from the propeller. Non-cavitating noise reduction is crucial for submarine stealth and survivability. Recently, several studies have been conducted on the use of flexible propellers as a means of reducing non-cavitating noise. However, there are no studies on the use of flexible propellers with adaptive characteristics to reduce noise in wake fields. Thus, this study investigated the noise reduction effect of adaptive characteristics on non-cavitating noise for the flexible propeller in the wake field. Numerical investigations on the main propeller variables were conducted based on the proposed procedure using fluid-structure interaction and acoustic analysis models. The results were compared with those of rigid propellers to determine the possible reasons for noise reduction. Finally, the acoustic analysis results of the flexible propeller were compared with those of the rigid propeller to reveal the effectiveness of the adaptive characteristics.