High-speed visualization of cavities, arising in a slit channel of complex shape.

The article presents the results of an experimental study of the cavitation flow around the NACA 0012 series foil in a slit channel with a width of 1.2 mm. The aspect ratio of the streamlined body was 0.02. To identify the main features of the two-phase flow, high-speed visualization was performed using the Photron FASTCAM NOVA S12 camera with a sampling frequency of 20 kHz. The internal structure of cavities was detected. The main frequencies of cavities formation in the flow were determined using digital processing of visualization data. The close location of the channel walls was shown to significantly affect the return flow propagation under the cavity and its separation. [ABSTRACT FROM AUTHOR]