The Influence of Variable Flow Velocity on Unsteady Airfoil Behavior

The exact theory of unsteady airfoil aerodynamics in a periodically varying free-stream of Isaacs is generalized to include arbitrary location of pitch axis, infinite number of pitch harmonics, and infinite number of plunge motion harmonics. The indicial method is extended to account for these effects. The results are compared to simplified theories. The accuracy of the extended indicial method is validated with the exact solution.

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