Low-Speed Investigation of the Stalling of a Thin, Faired, Double-Wedge Airfoil with Nose Flap
Abstract
The stalling characteristics of a 4.23-percent-thick,faired, double-wedge airfoil section with and without a plain nose flap were investigated. Flap chords equal to 12, 16, 20, and 25 percent of the airfoil chord were tested. Results of force and pressure-distribution measurements as well as studies of the boundary layer are presented for a Reynolds number of 5,800,000 and a Mach number of 0.17. The basic airfoil section stalled as a result of separation of flow from the entire upper surface. The flow separation first occurred at the leading edge at a small angle of attack and was followed by reattachment of the flow to the surface a short distance downstream. The chordwise extent of separated flow increased with increase in angle of attack until the flow was separated from the entire upper surface at the initial lift peak. With the nose flap deflected, the separation of the flow was delayed to higher angles of attack. With the nose flap deflected 20 deg or less, the stall was similar to that for the basic airfoil. For nose-flap deflect ions greater than 20 deg, flow separation starting from the trailing edge was also encountered and maximum lift was determined by combined leading and trailing edge separation. No significant differences in stalling characteristics were noted for the range of flap-chord ratios investigated.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1950
- Accession Number
- ADA380497
Entities
People
- John M. Altman
- Leonard M. Rose
Organizations
- National Aeronautics and Space Administration