Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
Published: 2018-07-17
Total Pages: 86
ISBN-13: 9781722870737
DOWNLOAD EBOOK →Three planar, untwisted wings with the same elliptical chord distribution but with different curvatures of the quarter-chord line were tested in the Langley 8-Foot Transonic Pressure Tunnel (8-ft TPT) and the Langley 7- by 10-Foot High-Speed Tunnel (7 x 10 HST). A fourth wing with a rectangular planform and the same projected area and span was also tested. Force and moment measurements from the 8-ft TPT tests are presented for Mach numbers from 0.3 to 0.5 and angles of attack from -4 degrees to 7 degrees. Sketches of the oil-flow patterns on the upper surfaces of the wings and some force and moment measurements from the 7 x 10 HST tests are presented at a Mach number of 0.5. Increasing the curvature of the quarter-chord line makes the angle of zero lift more negative but has little effect on the drag coefficient at zero lift. The changes in lift-curve slope and in the Oswald efficiency factor with the change in curvature of the quarter-chord line (wingtip location) indicate that the elliptical wing with the unswept quarter-chord line has the lowest lifting efficiency and the elliptical wing with the unswept trailing edge has the highest lifting efficiency; the crescent-shaped planform wing has an efficiency in between. Mineck, Raymond E. and Vijgen, Paul M. H. W. Langley Research Center...
Author: Thomas C. Kelly
Publisher:
Published: 1957
Total Pages: 82
ISBN-13:
DOWNLOAD EBOOK →Pressure data have been obtained in the Langley 8-foot transonic tunnel at Mach numbers from 0.80 to 1.115 and angles of attack from 0 to 20 degrees for wing-body configurations employing a thin trapezoidal wing in combination with basic and indented bodies. The wing had 26.6 degrees sweepback of the quarter-chord line, an aspect ratio of 2.61, a taper ratio of 0.211, and 2-percent-thick symmetrical circular-arc airfoil sections parallel to the plane of symmetry. Results are also presented for the basic body alone. Reynolds numbers for the tests were on the order of 2,600,000, based on the wing mean aerodynamic chord.