CFD-based analyses for a slow speed manoeuvrability model

In the context of the low speed and high drift angles manoeuvres, a limited number of experimental test cases are available in open literature. Consequently, the ability to reliably predict the hull forces (and the related hydrodynamic coefficients) via computational fluid dynamics calculations may represent a significant added value to further tune or to generate new simplified hull forces models to be employed in a manoeuvring code. Even if some applications can be found in the literature for selected cases and conditions, as those considered in the present work, a more systematic comparison is mandatory to confirm the reliability of these numerical approaches. In light of this, in the present work a systematic application of the open-source viscous-based flow solver OpenFOAM to predict forces at low-speed manoeuvring conditions for two ship test cases (the KCS and the KVLCC) is presented. The proposed numerical setup, specifically designed to be applied in the early ship design stage (limiting computational effort), shows a satisfactory accuracy to cope with the strong off-design conditions related to these specific ship operative conditions.