In the present paper, we compare two different computation methods for the simulation of leading edge cavitation. In the first one, known as interface tracking method, the cavity interface is taken as a free surface boundary and the calculation is performed in a single phase flow. The cavity shape is then determined apart from the flow calculation using an iterative procedure. The second method is based on the socalled interface-capturing law state model, assuming a constant enthalpy during the vaporization and condensation processes. Both methods are tested in the case of an isolated Naca 0009, 2-D hydrofoil. Both models gave good prediction of the cavity length and pressure distribution. Moreover, results obtained with the Interface-tracking one predict well the pressure distribution near the cavity detachment. Either methods do not allow a good prediction of the drag coefficient nor the drop of the lift due to cavitation. We have also performed an insight experimental investigation of the onset and detachment of a leading edge cavitation. We have demonstrated how the water may withstand negative pressure upstream to the cavity while the pressure measured in the cavity is almost equal to the vapor pressure. Furthermore, flow visualization clearly shows that a well developed leading edge cavitation turns into bubble cavitation in a continuous way when specific flow parameters are gradually changed and we suppose that the cavity aspect depends highly of the vapor generation rate at its detachment location. The negative pressure measured upstream to the cavity detachment may thus be explained by the dynamic delay of vaporization due to inertia. Owing to those results, we have summarize the actual cavitation modelisation need and made a perspective of future research.

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