Cavitation Inception in Turbulent Flows Around a Hydrofoil

摘要

The phenomenon of cavitation inception around a hydrofoil is studied experimentally. The flow velocities around the foil are measured by a laser doppler velocimetry (LDV). The inception cavitation aspects are observed by using a high-speed video camera. In the experiment, the Reynolds number is fixed at a value of 7.0 X 10~5. The boundary layer around the foil undergoes turbulent flow under the experiment condition. The LDV measurement results show that the flow in the boundary layer around the foil doesn' t separate from the surface. It is found that the cavitation inception in non-separated turbulent flow is related to the coherent structures in the boundary layer. It is clear that the turbulent bursting and the hairpin-shaped vortex structure accompany the incipient cavitation.