@inproceedings{1f5cfd7ff8e34db98049a2e8caebbbdf,
title = "Frequency analysis of surface pressures on an airfoil after stall",
abstract = "At high angles of attack airfoils can be considered as bluff bodies and their shedding frequency can be important to designers if it becomes too close to the natural frequency or a harmonic of the natural frequency of the object. This paper details the results from a thick, symmetric airfoil, a NACA 0021 section, at a Reynolds number of 2.70 × 105. At high angles of attack shedding frequencies were found in both the lift and the drag. The main frequency was at half the frequency of the secondary frequency as would be expected for a bluff body although the asymmetry in the wake caused both frequencies to be present in the lift and drag. These frequencies could be scaled by the width of the chord normal to the freestream such that the Strouhal number was nearly constant with angle of attack. The major shedding peak occurred at an angle of attack of 50 degrees, predominately in the lift.",
author = "Swalwell, {K. E.} and J. Sheridan and Melbourne, {W. H.}",
year = "2003",
month = dec,
day = "1",
doi = "10.2514/6.2003-3416",
language = "English",
isbn = "9781624100925",
series = "21st AIAA Applied Aerodynamics Conference",
publisher = "American Institute of Aeronautics and Astronautics",
booktitle = "21st AIAA Applied Aerodynamics Conference",
address = "United States of America",
note = "21st AIAA Applied Aerodynamics Conference 2003 ; Conference date: 23-06-2003 Through 26-06-2003",
}