The study of the total resistance of a submerged body is a matter of interest not only for the development of submerged vehicles like submarines or ROV, but also for the study of particular appendages that are fitted on a vessel, like a sonar dome or the under-keel of a sailing yacht. For this purpose RANS calculations can give an accurate estimate of the resistance without too much calculation effort. To perform an accurate estimate, a validation study, using STARCCM+ solver, has been carried out on a standard geometry of the 58 Series. The validated mesh has been used for the resistance evaluation of a new body.