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Aerodynamic coefficients in generalized unsteady thin airfoil theoryTwo cases are considered: (1) rigid body motion of an airfoil-flap combination consisting of vertical translation of given amplitude, rotation of given amplitude about a specified axis, and rotation of given amplitude of the control surface alone about its hinge; the upwash for this problem is defined mathematically; and (2) sinusoidal gust of given amplitude and wave number, for which the upwash is defined mathematically. Simple universal formulas are presented for the most important aerodynamic coefficients in unsteady thin airfoil theory. The lift and moment induced by a generalized gust are evaluated explicitly in terms of the gust wavelength. Similarly, in the control surface problem, the lift, moment, and hinge moments are given as explicit algebraic functions of hinge location. These results can be used together with any of the standard numerical inversion routines for the elementary loads (pitch and heave).
Document ID
19800053864
Document Type
Reprint (Version printed in journal)
Authors
Williams, M. H. (Princeton University Princeton, N.J., United States)
Date Acquired
August 10, 2013
Publication Date
July 1, 1980
Publication Information
Publication: AIAA Journal
Volume: 18
Subject Category
AERODYNAMICS
Funding Number(s)
CONTRACT_GRANT: NSG-2194
Distribution Limits
Public
Copyright
Other