Accession Number : ADA118190

Title :   Experimental Performance of a Flapped Hydrofoil in Calm Water at Low Froude Numbers.

Descriptive Note : Final rept.,

Corporate Author : DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD

Personal Author(s) : Wilson,Michael B

PDF Url : ADA118190

Report Date : Jun 1982

Pagination or Media Count : 99

Abstract : Results of an experimental investigation are presented for the subcavitating hydrodynamic force performance of an aspect ratio 6, NACA 64 A010 foil section, plain-flapped, rectangular planform hydrofoil. The forward-leading sting-supported foil model was operated in calm water in the speed range of chord Froude numbers 1.22 to 4.23, at five depth-to-chord submergence ratios varying from 0.25 to 4.0. The results, presented in coefficient form, include the basic measured foil-along lift and drag, increments and flap effectiveness due to flap deflection, and the inferred variation of hydrofoil drag-due-to-lift for lift coefficients as high as 1.0. These data cover an important low Froude number speed regime not normally included in published hydrofoil performance experiments. Comparisons are made between the experimental results for residual drag and two different analytical prediction schemes for the hydrofoil total drag-due-to-lift. It is shown that experimental values for residual drag are bounded below and above by the two prediction methods considered, and that the discrepancies are largest at low Froude numbers. (Author)

Descriptors :   *Hydrofoil craft, Lift to drag ratio, Flaps(Control surfaces), Deep submergence, Angle of attack, Hydrodynamic control surfaces, Deflection

Subject Categories : Marine Engineering
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE