• cavitation
• ventilation

This thesis is included in the cooperation between the University of Pisa, the French company Syroco and Cubitlab, which aims at developing the design of the new Moonshot#1 boat in order to break the world sailing speed record by reaching 150 Km/h.
The aim of this thesis is to define a CFD procedure to correctly simulate the interaction phenomenon between cavitation and ventilation on a semi-submerged cylinder moving through sea water, by carrying on previous research activities focused on cavitation and ventilation phenomena considered separately.
In particular, starting from the results of the simulations carried out previously, it has been set up a CFD campaign of RANS simulations in which the cavitation and the ventilation phenomena have been investigated, in order to find out the best numerical methods to simulate them, which turned out to be, for cavitation, the use of the Singhal cavitation model together with the k-ε turbulence model, while for ventilation, the use of the All y+ wall treatment together with the SST Menter k-ω turbulence model.
After achieving these results, it has been set up a CFD campaign of simulations in which the phenomenon of cavitation has been added to the ventilation one, for trying to simulate their interaction. To do this, the cavitation model has been activated in the ventilation simulations and the simulations have been carried out firstly using an unsteady RANS approach and then using a DES approach, in order to investigate the effect of turbulence modelling.