Pages 71-79
Viscous effects at low Froude numbers exerted on Wigley Geosim Models (2.5^m:Univ. of Tokyo, 4^m:SRI, 6^m:IHI) in the 17th ITTC cooperative works are analyzed. Double model flows are assumed and 3-D boundary layer equations of integral method are applied to evaluate frictional resistance as well as viscous pressure resistance, sinkage force and trim moment. Through the analysis, it is concluded that; 1. 3-D boundary layer calculation based upon small crossflow assumption is valid for thin mathematical forms of Wigley models. Displacement thickness, momentum thickness and hull surface pressure are well reproduced on the computation. Results coincide well with measured. 2. Scale effect on form factors worked out experimentally are also firmed through the calculation of viscous pressure resistance. Reynolds number effect exists regarding pressure on hulls at the stern which can be visualized as the small difference of wave profiles.
