Accession Number : ADA312445

Title :   Experimental Analysis of the Wake of an Oscillating Airfoil.

Descriptive Note : Master's thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s) : Dohring, Claus M.

PDF Url : ADA312445

Report Date : JUN 1996

Pagination or Media Count : 148

Abstract : The wake of an airfoil which oscillates in pure plunge mode is investigated in a water tunnel over a wide range of reduced frequency and amplitude. The main focus of this study is the comparison of the experimentally determined wake geometry with numerical results from a potential flow code. The wake vortices are visualized by two-color dye injection and velocity profiles are measured with LDV upstream and downstream of the airfoil. Wake signatures are examined with regard to thrust or drag generation. There is a good agreement between calculated and experimental data of the vortical wavelength. At high plunge velocities both approaches show a loss of wake symmetry and the emergence of a dual mode wake behavior.

Descriptors :   *VORTICES, *WAKE, *AERODYNAMIC DRAG, THESES, COMPUTATIONAL FLUID DYNAMICS, FLOW VISUALIZATION, FLOW FIELDS, FLAPS(CONTROL SURFACES), LEADING EDGES, FREE STREAM, VISCOSITY, HYDRODYNAMICS, THRUST, REYNOLDS NUMBER, POTENTIAL FLOW, BOUNDARY LAYER FLOW, LASER VELOCIMETERS, WATER TUNNELS, TRAILING EDGES.

Subject Categories : Aerodynamics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE