Accession Number:

AD0867314

Title:

Experimental Investigation of Aerodynamic Phenomena in the Wake of a Rapidly Stalled Wing.

Descriptive Note:

Final rept. 5 Feb 68-5 Jun 69,

Corporate Author:

ALLIED RESEARCH ASSOCIATES INC CONCORD MA

Personal Author(s):

Report Date:

1970-02-01

Pagination or Media Count:

57.0

Abstract:

By means of wind-tunnel experiments, aerodynamic phenomena were investigated in the wake of a rapidly stalled two-dimensional wing. Experiments were performed to study the effect of wing pitch rate, model size, and leading edge details on vertical and horizontal perturbation velocities downstream of the wing. Large vertical wake velocities peak-to-peak values up to 160 fps, transient in nature, were measured during early times following a pitchup maneuver. The magnitude of this velocity was a function of the pitch rate parameter. Large steady-state buffeting velocities peak-to-peak values up to 160 fps were also measured in the wing wake. A result of particular significance to aircraft tail surface design was that the steady-state buffeting was strongly periodic throughout the tested Reynolds number range 680,000 to 1,360,000. A simplified dynamic analysis of the C-2A horizontal tail for a velocity input representative of the steady-state buffeting experimental results indicated that this condition could produce the large loads measured during flight test maneuvers. Author

Subject Categories:

  • Transport Aircraft
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE