Accession Number : AD0642621

Title :   THE EFFECTIVENESS OF A SPLITTER PLATE IN REDUCING TRANSVERSE OSCILLATIONS OF A FINITE CIRCULAR CYLINDER IN TURBULENT FLOW.

Descriptive Note : Research rept.,

Corporate Author : NAVY UNDERWATER SOUND LAB NEW LONDON CONN

Personal Author(s) : Welsh,Robert I.

Report Date : 30 SEP 1966

Pagination or Media Count : 93

Abstract : A right circular cylinder moving through a viscous fluid and oriented so that the longitudinal axis is normal to the flow is acted upon by drag forces, opposite to the direction of motion, and by alternating lift forces, transverse to the direction of motion. Studies on cylindrical bodies, having large-length-to-diameter ratios when end effects do not influence the spanwise flow pattern (infinite cylinders), show that the transverse forces are caused by vortex or shedding from the body at subcritical and transcritical Reynolds numbers and by the randomly turbulent wake at supercritical Reynolds numbers. It has been previously shown that a splitter plate placed in the wake behind infinite cylinders is an effective means of suppressing vortex shedding at subcritical and transcritical Reynolds numbers. This investigation studied the drag and oscillating lift forces at supercritical Reynolds numbers on a circular cylinder with a length-to-diameter ratio of 1.5 (i.e., a finite cylinder). Drag coefficients were computed and compared to those for infinite cylinders and were found to agree fairly well with the results of Delaney and Sorensen. A splitter plate with a chord length equal to one cylinder diameter was placed in three positions behind the cylinder, and drag and lift forces were measured to determine the best plate position for reducing drag and suppressing wake-induced transverse oscillations. (Author)

Descriptors :   (*TURBULENCE, CYLINDRICAL BODIES), DRAG, REDUCTION, OSCILLATION, HYDRODYNAMIC CONFIGURATIONS

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE