Experimental Study of Cavity Flow Behavior on a 2-D Hydrofoil

To obtain information on the cavity flow behavior, an experimental study of the external and internal flows of a cavity occurring on a 2-D hydrofoil was performed in a closed-type cavitation tunnel. The liquid phase velocities and their fluctuations in the flow field inside and outside the cavity were measured by using a Laser Doppler Velocimeter (LDV) in different cavitation states. In addition, the corresponding cavitation aspects were observed photographically by means of a xenon flach lamp with an exposure time of 1 μs and a high-speed video. The results show that the averaged velocity profiles inside the cavity are similar to those in the single phase boundary layer. However, strong fluctuation and intermittent reverse flow occur within the cavity, especially in the region near the bottom.