
Accession Number : AD0690945
Title : DEVELOPMENT AND EVALUATION OF A SECONDORDER WAVERESISTANCE THEORY.
Descriptive Note : Final rept.,
Corporate Author : STEVENS INST OF TECH HOBOKEN N J DAVIDSON LAB
Personal Author(s) : Eng,King
Report Date : AUG 1969
Pagination or Media Count : 79
Abstract : A new secondorder waveresistance theory for floating bodies is developed, and then assessed by application to a parabolic strut. The problem is treated as a potential flow problem with a centerplane distribution of sources to represent the body. However, the kinematical boundary condition is satisfied on the surface of the body. It is supposed that the beamlength ratio , t , is small and that the square of the disturbance velocities which appeared in Bernoulli's equation on the free surface is given in terms of the components of the firstorder potential. It is also assumed that the solution of the source density, sigma, is in the form of an asymptotic series in t , and the solution for sigma is obtained up to the order of t sq. The wave resistance is then computed on the basis of the improved source density and the correction arising from the improved representation of the free surface. It is found that at low Froude number the expansion scheme used by Sisov, by Maruo, by Yim, and by Eggers, can give negative resistance if the beamlength ratio is not small enough. Therefore, a new definition is adopted; that is, the secondorder wave resistance is based on the improved disturbance potential without expansion of the amplitude function of the waveresistance integral. (Author)
Descriptors : (*FLOATING BODIES, *DRAG), HYDRODYNAMICS, SHIP STRUCTURAL COMPONENTS, SUPPORTS, PARABOLIC BODIES, THEORY, MATHEMATICAL ANALYSIS, THESES
Subject Categories : Marine Engineering
Fluid Mechanics
Distribution Statement : APPROVED FOR PUBLIC RELEASE