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A wake singularity potential flow model for airfoils experiencing trailing-edge stall

Published online by Cambridge University Press:  26 April 2006

W. W. H. Yeung
Affiliation:
Nanyang Technological University, Singapore
G. V. Parkinson
Affiliation:
Department of Mechanical Engineering, University of British Columbia, Vancouver, Canada V6T 1Z4

Abstract

An incompressible inviscid flow theory for single and two-element airfoils experiencing trailing-edge stall is presented. For the single airfoil the model requires a simple sequence of conformal transformations to map a Joukowsky airfoil, partially truncated on the upper surface, onto a circle over which the flow problem is solved. Source and doublet singularities are used to create free streamlines simulating shear layers bounding the near wake. The model's simplicity permits extension of the method to airfoil-flap configurations in which trailing-edge stall is assumed on the flap. Williams’ analytical method to calculate the potential flow about two lifting bodies is incorporated in the Joukowsky-arc wake-singularity model to allow for flow separation. The theoretical pressure distributions from these models show good agreement with wind-tunnel measurements.

Type
Research Article
Copyright
© 1993 Cambridge University Press

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