Lift and drag penalties due to the ice shape were found and the surface pressure clearly showed that large separation bubbles were present. Surface pressure and wake data were taken on the airfoil clean, with forced transition and with a simulated glaze ice shape. A NACA 0012 model with interchangeable leading edges and pressure taps every one percent chord was used. The 15 indicates that the airfoil has a 15% thickness to chord length ratio: it is 15% as thick as it is long.An experimental study of the aerodynamics of a NACA 0012 airfoil with a simulated glaze ice accretion An experimental study was conducted in the Ohio State University subsonic wind tunnel to measure the detailed aerodynamic characteristics of an airfoil with a simulated glaze ice accretion. The NACA 0015 airfoil is symmetrical, the 00 indicating that it has no camber. įor example, the NACA 2412 airfoil has a maximum camber of 2% located 40% (0.4 chords) from the leading edge with a maximum thickness of 12% of the chord. Last two digits describing maximum thickness of the airfoil as percent of the chord.Second digit describing the distance of maximum camber from the airfoil leading edge in tenths of the chord.First digit describing maximum camber as percentage of the chord.The NACA four-digit wing sections define the profile by: These figures and shapes transmitted the sort of information to engineers that allowed them to select specific airfoils for desired performance characteristics of specific aircraft. Engineers could quickly see the peculiarities of each airfoil shape, and the numerical designator ("NACA 2415," for instance) specified camber lines, maximum thickness, and special nose features. By 1929, Langley had developed this system to the point where the numbering system was complemented by an airfoil cross-section, and the complete catalog of 78 airfoils appeared in the NACA's annual report for 1933. According to the NASA website:ĭuring the late 1920s and into the 1930s, the NACA developed a series of thoroughly tested airfoils and devised a numerical designation for each airfoil - a four digit number that represented the airfoil section's critical geometric properties. NACA initially developed the numbered airfoil system which was further refined by the United States Air Force at Langley Research Center. The NACA airfoil series is a set of standardized airfoil shapes developed by this agency, which became widely used in the design of aircraft wings. It played a crucial role in advancing aviation technology, including the development of airfoils, which are the cross-sectional shapes of wings and other aerodynamic surfaces. federal agency founded in 1915 to undertake, promote, and institutionalize aeronautical research. NACA stands for the National Advisory Committee for Aeronautics, which was a U.S. thickness 5: Camber 6: Upper surface 7: Trailing edge 8: Camber mean-line 9: Lower surface Profile lines – 1: Chord, 2: Camber, 3: Length, 4: Midline A: blue line = chord, green line = camber mean-line, B: leading-edge radius, C: xy coordinates for the profile geometry (chord = x axis y axis line on that leading edge) Wing shape Profile geometry – 1: Zero-lift line 2: Leading edge 3: Nose circle 4: Max.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |