Some parameters influencing the accuracy of the wave pattern resistance determination

The method for wave pattern resistance determination from wave pattern measurements in longitudinal cuts, in a tank of finite width, has been shown. The influence of the record length and the starting position with respect to the main hull stern, for a chosen trimaran configuration, on the accuracy of results has been analyzed. The record length represents a critical parameter in all methods for wave pattern resistance de-termination from wave pattern measurements in longitudinal cuts. Dissipation of results becomes significant if the record length is too short. It has been shown that the wave pattern resistance decreases considerably as the record length becomes longer, what physically has no sense. Performed numerical experiments with theo-retically generated waves show that the increase of the record length entails increase in the wave pattern resis-tance e.g. it converges to the theoretical value. Such behaviour can be attributed to the existence of certain physical phenomenon in the experiment that is not embraced by the present hydrodynamical model. For maximal disposable record length most of the experimentally obtained points lie within the confidence preci-sion error band.