DIVERGENCE ANALYSIS OF SWEPT HYDROFOILS--COMPUTER PROGRAM (SWDIVRG)

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 lumped-parameter approach, resulting in a matrix solution of the system. The bending and torsional displacements at 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 cantilever-beam constraints. The divergence speed is principally computed by an eigenvector iteration scheme. A convenient formulation and a plot are provided for estimating the hydrodynamic loading parameters for finite-span, surface-piercing hydrofoils. Also, a useful closed-form 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 closed-form solution, show good agreement with experimental model-divergence speeds.

• Corporate Authors:

  Naval Ship Research and Development Center

  Ship Acoustics Department
  Bethesda, MD  United States  20034
• Authors:
  • Caspar, J R
• Publication Date: 1974-4

Media Info

• Features: Appendices; References;
• Pagination: 80 p.

Subject/Index Terms

• TRT Terms: Bending; Hydrofoils; Loads; Moments (Mechanics); Stiffness; Torsion
• Old TRIS Terms: Bending stiffness; Hydrofoil loading; Surface piercing hydrofoils; Torsional moment
• Subject Areas: Design; Marine Transportation; Materials;

Filing Info

• Accession Number: 00054994
• Record Type: Publication
• Source Agency: Naval Ship Research and Development Center
• Report/Paper Numbers: #4245
• Files: TRIS
• Created Date: Jul 15 1974 12:00AM