Numerical and experimental fluid dynamics in the modern yacht design process

There are three main methods to assess the hydrodynamic characteristics of yachts, namely, viscous and inviscid numerical analysis, and experimental tests. Computational tools are now widely used in yacht design because of the rapid growth of high-powered computers during the last 10 years. Viscous computational fluid dynamic codes are now one of the most important tools in design offices, in marine and other fields, and in some fields they have completely replaced inviscid codes and experimental tests. A deeper awareness of the uncertainty of RANS code results is necessary, achievable with a rigorous application of a verification and validation process. The effectiveness of these three methods is discussed with regards to their application to yacht design of their hulls, hull appendages and propellers. The aim of this paper is to show that each of these three methods is very useful, having their own unique features, but the methods must be used with caution and a thorough understanding of their limitations, so as to provide a reliable suite of design tools.