Investigation of three-dimensional effects on a cavitating Venturi flow

• An unsteady 3D cavitation sheet is computed with DES and SAS turbulence models.
• 2D and 3D computations are performed and compared with experimental results.
• The 3D computations put in evidence a low frequency, which is absent from 2D computations.
• The low frequency is in agreement with recent experimental analysis.

A numerical investigation of the behaviour of a cavitation pocket developing along a Venturi geometry has been performed using a compressible one-fluid hybrid RANS/LES solver. The interplay between turbulence and cavitation regarding the unsteadiness and structure of the flow is complex and not well understood. This constitutes a determinant point to accurately simulate the dynamic of sheet cavities. Various turbulent approaches are tested: a new Scale-Adaptive model and the Detached Eddy Simulation. 2D and 3D simulations are compared with the experimental data. An oblique mode of the sheet is put in evidence.