Supercavitating vehicles need to be supplied with an artificial cavity through ventilation until they accelerate to conditions at which a natural supercavity can be sustained. Therefore the gas injection is required to have supercavitation at velocities lower than those needed for natural supercavitation. A numerical unsteady approach is fallowed to simulate ventilated cavitation behind a two-dimensional wedge (chord 60.5 mm, base 17 mm). In this study the liquid-gas interface is modeled, using the volume of fluid (VOF) method based on young’s algorithm. Different free stream velocities are considered in this simulation. The transient Navier-Stokes equations are solved along with an equation to track the cavity interface. Turbulent fluctuations in the velocity field are modeled using the Reynolds Averaged Navier-Stokes (RANS) methodology. Turbulence is assumed to be isotropic and RNG k - e turbulence model is used in this investigation. The results for variation of the cavity lengths with the cavitation numbers are compared to the results of an empirical formula obtained using available experimental data. The comparison shows that the computational and experimental results are in good agreement with each other. The simulation shows that, the cavity length will increase by decreasing the cavitation number and is independent of the free stream velocity. The main dimensionless factor which plays significant role in the prediction of the cavity lengths is the cavitation number.

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