Accession Number : AD0700251

Title :   ROLL DAMPING OF CIRCULAR CYLINDERS WITH AND WITHOUT APPENDAGES.

Descriptive Note : Research and development rept.,

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

Personal Author(s) : Gersten,Alvin

Report Date : OCT 1969

Pagination or Media Count : 65

Abstract : A research program established to provide scaling laws for roll damping involves testing five circular cylinders ranging from 3 in. to 4 ft in diameter. The report presents the results of experiments conducted on the fourth cylinder in the series, which has a 2-ft diameter and which, like those tested before it, was oscillated freely at zero forward speed. The experiments were carried out with the cylinder suspended vertically in the water both with and without appendages, and with the bare cylinder floating horizontally. In this way, the various components of damping can be isolated. Log decrements and energy loss per cycle for the bare cylinder, as well as energy loss and moment coefficients for the appendaged cylinder, are presented herein. (Author)

Descriptors :   (*SUBMARINES, HYDRODYNAMICS), (*ROLL, DAMPING), SUBMARINE MODELS, CYLINDRICAL BODIES, MODEL TESTS, PREDICTIONS, HYDRODYNAMIC CONFIGURATIONS

Subject Categories : Submarine Engineering
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE