Cavity dynamics and vibrations of a flexible hydrofoil in the cavitating flow

The objective of this paper is to investigate the influence of fluid-structure interaction on the cavity dynamics and the vibrations around a flexible hydrofoil by comparing the experimental results of a rigid hydrofoil. Cavitation behavior, vibrations, and lifts are obtained by a synchronized measured system utilizing a high-speed camera, lift measurement, and a portable laser vibrometer. The nose-up twisting deformation results in an increase in the effective angle of attack, which leads to an increase in cavity length and a reduction of cloud cavity shedding frequency. It also accelerates the transition of the cavitation regimes and shedding mechanism of cloud cavities with the decrease in cavitation number, together with the amplification of vibration velocity, and the suppression of higher-frequency oscillations.