The estimation of the hydrodynamic performances of a sailing yachts are not easy to be determined in an unambiguous way because the presence of the wind as propulsive force leads to a strong coupling between all the six degrees of freedom of the vessel, even in reasonably calm water. This kind of situation makes really hard to establish the final resistance of the hull and makes even more complicated the selection of a specific situation to perform a hull form optimisation. Once a first assessment of the resistance quality of a sailing yacht should be done, a simple approximation in three degrees of freedom can be made, giving indications also to motor cruise performances of the sailing yacht. STARCCM+ solver for RANS equations has been used to evaluate the total hull resistance. To perform an accurate calculation, a validation study has been executed on a model of the Delft Systematic Yacht Hull Series. On the validated mesh it was possible to perform calculations at the design speed, aimed to study new hull geometries to reduce the total resistance. On the final hull, all the speed range of interest has been tested and compared with results coming from systematic series and slender body theory.
