Accession Number : AD0742071

Title :   A Theoretical Study of the Effect of Viscosity on Wave Resistance.

Descriptive Note : Final rept.,

Corporate Author : STEVENS INST OF TECH HOBOKEN N J DAVIDSON LAB

Personal Author(s) : Kim,C. H. ; Breslin,J. P.

Report Date : APR 1972

Pagination or Media Count : 41

Abstract : A simple mathematical model is proposed for the effect of viscosity on the wave resistance of a ship, and evaluated within the frame of linearized theory. The present investigation considers a Joukowski strut infinitely deep in a uniform stream and the viscosity effect is considered as represented by vortex sheets shed abaft the stern. The vortex sheets being shed behind the strut are represented equivalently by a distribution of doublets. The image of the vortex system, as well as the image system of the doublet distribution, is correspondingly placed within the hull contour. The wave resistance due to the system of singularities representing wake, image and hull consists of six components, coupled and uncoupled. A numerical calculation has revealed that the coupled terms of the wake-hull and image-hull contribute predominantly to the reduction of the wave resistances and this was more accentuated as the width of the separation points was increased. (Author)

Descriptors :   (*SHIP HULLS, DRAG), (*WAKE, MATHEMATICAL MODELS), HYDRODYNAMICS, VORTICES, VISCOSITY, STATISTICAL DISTRIBUTIONS, NUMERICAL ANALYSIS, FLOW SEPARATION

Subject Categories : Marine Engineering
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE