Accession Number : AD0661866

Title :   INFLUENCE OF SCALE RATIO, ASPECT RATIO, AND PLANFORM ON THE PERFORMANCE OF SUPERCAVITATING HYDROFOILS.

Descriptive Note : Research and Development rept.,

Corporate Author : NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER WASHINGTON D C HYDROMECHANICS LAB

Personal Author(s) : Dobay,Gabor F.

Report Date : AUG 1967

Pagination or Media Count : 93

Abstract : Seven hydrofoil models, having geometrically similar section shapes, were tested to evaluate the effect of scale, aspect ratio, and planform on the performance of supercavitating hydrofoils. No appreciable scale effect was found for scale ratios up to 3 in the fully-cavitating flow region. The experimental results indicate that the induced angle of attack, due to finite aspect ratio, reduces more rapidly in cavitating flow than is experienced in fully wetted flow as the aspect ratio increases. Also, the influence of the tip vortex on the effective aspect ratio is different for different flow regions. Judging from the overall behavior of these hydrofoils, two major conclusions can be drawn: (1) little improvement is achieved in the overall performance of the hydrofoil by increasing the aspect ratio above 3, and (2) moderate taper ratio seems to be advantageous in view of the overall performance of supercavitating hydrofoils. (Author)

Descriptors :   (*HYDROFOILS, PERFORMANCE(ENGINEERING)), ASPECT RATIO, SCALE, CAVITATION, ANGLE OF ATTACK, VORTICES, TAPER, MODEL TESTS

Subject Categories : Marine Engineering
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE