Accession Number : ADA137744

Title :   Measurements of the Near Wake of an Airfoil in Unsteady Flow.

Descriptive Note : Interim rept.,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF AERONAUTICS AND ASTRONAUTICS

Personal Author(s) : Covert,E E ; Lorber,P F ; Vaczy,C M

PDF Url : ADA137744

Report Date : Jan 1983

Pagination or Media Count : 13

Abstract : A series of measurements has been made of the velocities in the near wake of an airfoil in an unsteady flow generated by rotating an elliptic cylinder near the trailing edge. Ensemble averages of the tangential and normal velocity components and of 3 Reynolds stresses were determined for reduced frequencies based on semichord up to 6.4, angles of attack of 0 and 10 degrees, Reynolds numbers of 700,000 and 1,450,000, and chordwise positions 1.025 x/c 1.2. In this region the airfoil wake is distinct from the wake of the elliptic cylinder. The mean and unsteady velocities and Reynolds stresses diffuse rapidly so that the distinction between the contributions due to the two boundary layers on the airfoil surfaces, apparent at x/c=1.025, has largely disappeared by x/c=1.20. (Author)

Descriptors :   *Wake, *Trailing edges, *Unsteady flow, Turbulent boundary layer, Airfoils, Cylindrical bodies, Rotation, Ellipses, Turbulent flow, Velocity, Near field, Hot wire anemometers, Wind tunnel tests, Reynolds number

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE