Accession Number:

AD0256508

Title:

A STUDY OF FLUTTER AT LOW MASS RATIOS WITH POSSIBLE APPLICATION TO HYDROFOILS

Descriptive Note:

Corporate Author:

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON D C

Personal Author(s):

Report Date:

1961-05-01

Pagination or Media Count:

1.0

Abstract:

Experimental flutter-test results for some flexible cantilever-wing models partly submerged in water are presented. The results tend to corroborate theoretical predictions of a stable region at low ratios of structural mass to fluid mass. Theoretical studies indicate this dynamic stability to be closely associated with the presence of fluid damping forces. An explicit expression is presented which defines the lowest mass ratios for which representative section flexure-torsion flutter solutions are obtainable as a function of the various structural parameters. Classical flutter of hydrofoils is possible, especially for heavy sections with the center of gravity located far aft. Theoretical indications are that the flutter boundary at low mass ratios is very sensitive to small differences in the various theories. Inclusion of sweep in a modal analysis resulted in flutter solutions in the low mass-ratio range where none had previously been obtained. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE