
Accession Number : AD0779844
Title : Divergence Analysis of Swept HydrofoilsComputer Program (SWDIVRG).
Descriptive Note : Final rept.,
Corporate Author : NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD
Personal Author(s) : Caspar,John R.
Report Date : APR 1974
Pagination or Media Count : 79
Abstract : A systematic approach is described by which divergence characteristics of swept or unswept hydrofoils may be calculated. The computer program, called SWDIVRG, developed to do the calculations makes use of a lumpedparameter approach, resulting in a matrix solution of the system. The bending and torsional displacements any of N stations along the hydrofoil span can be calculated at speeds less than divergence. Bending and torsional moments can be calculated for the condition of cantileverbeam constraints. The divergence spe d is principally computed by an eigenvector iteration scheme. A convenient formulation and a plot are provided for estimating the hydrodynamic loading parameters for finitespan, surfacepiercing hydrofoils. Also, a useful closedform divergence formulation, which considers submergence level, has been derived for the special case of a uniform cantilever strut or foil. Test calculations of airfoil models and one hydrofoil model, using both SWDIVRG and the closedform solution, show good agreement with experimental modeldivergence speeds. (Author)
Descriptors : *Hydrofoil craft, *Hydrofoils, FORTRAN, Bending moments, Torsion, Lifting surfaces, Hydrodynamics, Mathematical models, Computer programs
Subject Categories : Marine Engineering
Fluid Mechanics
Distribution Statement : APPROVED FOR PUBLIC RELEASE