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The initial lift and drag of an impulsively started airfoil of finite thickness

Published online by Cambridge University Press:  20 April 2006

Chuen-Yen Chow  and
Ming-Ke Huang
Chuen-Yen Chow
Affiliation:
Department of Aerospace Engineering Sciences, University of Colorado, Boulder, Colorado 80309, USA
Ming-Ke Huang
Affiliation:
Department of Aerospace Engineering Sciences, University of Colorado, Boulder, Colorado 80309, USA
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Abstract

The method of apparent masses is utilized to compute the initial lift and drag of an airfoil that starts impulsively from rest. Analytical solutions are obtained for in viscid incompressible flow past a slightly cambered airfoil at a small angle of attack. For a Joukowski airfoil with a cusped trailing edge, it is found that increasing camber or angle of attack will cause increases in both initial lift and drag, whereas increasing thickness will result in an opposite effect. Effects of trailing-edge angle are examined by considering the symmetric Kármán-Trefftz airfoil. The result shows that both lift and drag vanish at the initial instant if the airfoil has a finite trailing-edge angle.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 118 , May 1982 , pp. 393 - 409
Copyright
© 1982 Cambridge University Press

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