A study of ship viscous resistance has been carried out. The study follows the practical approach in which viscous resistance is obtained from an estimate of the skin friction coefficient together with the application of a suitable form factor.
Reanalysis of Hughes' original data was performed. Variables affecting form factor with regard to correlation between hull parameters are discussed and a new formula for predicting form factor has been derived using statistical analysis methods. Its accuracy is compared with existing empirical formulae as well as with tank test results.
In order to provide further validation data, measurements of total and wave pattern resistance were carried out on a model. Form factor in this case was determined both from a Prohaska plot of the low speed measurements and from (Ct-Cwp)/Cf. The results of these tests are discussed together with other possible influence on the results such as the effects of scaling and water depth.
Overall conclusions are drawn concerning the estimation of viscous resistance and form factors, and recommendations made for further work.
