Ventilated supercavitation is hydrodynamic phenomenon where injected air forms a large bubble around a high-speed submerged body, reducing drag friction to enhance its movement. The study of cavitating flows becomes more critical when the supercavity is near the free surface, and the interaction between the supercavity and the free surface waves also becomes significant. In this study, the behavior of the ventilated supercavity and the free surface waves at high Froude numbers and different submersion depths have been investigated. A numerical simulation approach has been used to solve the Navier-Stokes equations, and the accuracy of the predicted results has been verified by comparing them with available experimental data, in terms of the supercavity characteristics and free surface waves. The results indicate that the supercavity size is affected by both submersion depth and Froude number, simultaneously. Additionally, as the Froude number increases, the submersion depth at which the free surface effect on the supercavity shape becomes negligible also increases. Moreover, in areas near the free surface, unlike fully submerged conditions, the supercavity length increases with depth. The results also show that, three types of free surface wave patterns are formed, depending on the intensity of the first and second wave systems.

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