Validazione di un modello computazionale per lo studio di eliche all'interno di tunnel di cavitazione

The present technical paper describes the developed theoretical and numerical model to address the flow around an isolated propeller operating as in a hydrodynamic cavitation testing tunnel. The fluidynamic model is based on a Boundary Element Model, recognised to be a robust with respect to computational burden. It is applied to address the flow around generalised rotoric/statoric systems through the solution in terms of the scalar velocity potential. Mutual bodies interaction coefficients are decomposed by means of Fourier serie to limit computational burden, stated a preliminary analysis on the error introduced. The resulting equation system is solved through an iterative procedure. Main quantities as thrust and torque, induced velocity and pressure in the field are calculated based on the solution. The confinement effect of tunnel walls is also quantified. The model results are analised in terms of confinement effect of tunnel walls on propeller loads and on the pressure fluctuation on tunnel walls. In particular, numerical results are validated against predictions of different numerical models and experimental data of the propulsive configuration.