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This paper presents a selection of CFD investigations on ship and propeller hydrodynamics performed in the frame of an extensive benchmarking activity, presently undertaken in the frame of the OpenSHIP Project - Highly reliable CFD simulations for the prediction of the hydrodynamic performance of the hull-propeller system with OpenSource software - co-financed by the ERDF - European Regional Development Fund - Friuli Venezia Giulia Region Operational Programme 2007 - 2013. Spilling breaking and non-breaking waves induced by a foil at constant speeds underneath the free surface are presented first. The wake at the propeller disk of a double model hull – MOERI KCS - is then analyzed, and finally the numerical predictions of the propulsive characteristics of two different model scale propellers are presented. All the simulations are carried out using the OpenFOAM-2.1.0 CFD package, and the numerical results are compared with available experimental data.

In this paper the numerical simulations of the flow around an elastically-mounted circular cylinder with one degree of freedom (1-DOF) with small damping parameter and small mass ratio are presented. The simulations are performed for subcritical Reynolds numbers ( 2 . 0 ⋅ 1 0 3 Re 1 . 3 1 0 4 ), using the URANS (Unsteady Reynolds Averaged Navier Stokes) approach in combination with the SST (Shear Stress Transport) turbulence model. The simulations are carried out on 3D as well as 2D meshes. From the overall results it seems that the bi-dimensional approach could be effectively applied in the lower branch, while major discrepancies are present in the upper branch. The detailed analysis of the wake flow characteristics shows that the three dimensionality of the flow is stronger in the transition zones between the different branches. The extensive comparison between the computational simulations and the experimental results presented in this paper could be considered the “start point” in order to select the proper grid model depending on the requested accuracy.

SOPHYA – Seakeeping Of Planing Hull YAchts - is a joint academic-industrial research project co-funded by EU through the Regional Administration of Friuli-Venezia Giulia Region (Italy), whose aim is to investigate the correlation between the sea state and the performance of planing hulls in terms of seakindliness, safety and energy performance. The tools adopted by the project are CFD simulations, model and full scale tests in calm water and wavy conditions. The hull selected for these activities is a 65 footer from Monte Carlo Yachts s.p.a. As for the full scale sea trials, some of the partners of SOPHYA project, namely MICAD (design office), Monte Carlo Yachts (builder) and the University of Trieste, in collaboration with the National Institute of Oceanography and Experimental Geophysics (OGS) and the University of Naples Federico II, planned, designed and carried out comprehensive full scale tests that include the simultaneous measurement of on-site sea state, of torque and rpm at the propeller shafts, of fuel consumption and of accelerations and angular displacements on board. The use of high fidelity/resolution sea-state forecast, running daily at the University of Trieste, allowed to plan the activities in order to carry out the full scale tests with the target significant wave height provided by the end users of the boat. This work describes the full scale tests conducted within SOPHYA Project, in particular those related to ship motions in waves. Some of the results obtained so far from the analysis of the data are presented.