Accession Number : AD0780228

Title :   Linear Design of Supercavitating Cascade Sections,

Corporate Author : NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD

Personal Author(s) : Yim,Bohyun ; Higgins,Laurie

Report Date : MAR 1974

Pagination or Media Count : 43

Abstract : A method for designing two-dimensional supercavitating cascade sections is developed. Linear superposition is used to produce a foil section that has a low drag-to-lift ratio and yet has a reasonably thick cavity. Foils of three elementary pressure distributions are analyzed separately; i.e., a low drag-pressure distribution, a concentrated leading-edge pressure, and a flat plate with angle of attack. The double spiral vortex model is taken for the cavity termination. The pressure distributions are superposed to give the desired lift and cavity thickness for any specified cavity length and cascade geometry. The cavity drag, the cavitation number, and the foil-cavity shape are the main output of the computer program. Cascade parameters are shown to strongly influence the previously mentioned quantities as well as the leading-edge shape. (Author)

Descriptors :   *Cascade structures, *Cavitation, Supercavitating propellers, Pumps, Hydrofoils, Lift to drag ratio, Cavities, Linear programming

Subject Categories : Marine Engineering
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE