Accession Number:

AD0785230

Title:

Two-Dimensional Subsonic Evaluation of a 15-Percent Thick Circulation Control Airfoil with Slots at Leading and Trailing Edges,

Descriptive Note:

Corporate Author:

NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT

Personal Author(s):

Report Date:

1974-07-01

Pagination or Media Count:

64.0

Abstract:

A 15-percent-thick circulation control elliptical airfoil section with slots at both leading and trailing edges for tangential blowing was evaluated in a subsonic wind tunnel to determine its potential for high-speed 300-400 knot helicopter rotor systems. Fore-and-aft slot utilization were determined by local flow direction over the blade as it revolved around the azimuth. Aerodynamic performance was not affected by the addition of an unblown leading edge slot except beyond the usable positive angle of attack range where some loss in lift and increase in drag were noted. At equal plenum pressures, simultaneous blowing from the leading and trailing edges resulted in a decrease in lift, an increase in drag, and a more positive pitching moment than for trailing edge blowing alone. Modified author abstract

Subject Categories:

  • Aerodynamics
  • Helicopters

Distribution Statement:

APPROVED FOR PUBLIC RELEASE