Camber Effects on the Leading-Edge Suction, Forces, and Vortex Dynamics of Unsteady Airfoils
Publication: Journal of Aerospace Engineering
Volume 37, Issue 5
Abstract
Understanding the effect of airfoil geometry on the criticality of leading-edge suction is key to modeling the leading-edge vortex (LEV) dynamics of unsteady airfoils in a simple and robust manner. The current work aimed at investigating the dependency of the leading-edge suction parameter (LESP), a nondimensional measure of the leading-edge suction, at its critical value, which is indicative of leading-edge vortex initiation, on airfoil camber. Computational data for six NACA XX12 series airfoils with varying camber magnitude and maximum camber location at Reynolds numbers 30,000 and 3 million were analyzed. Observations indicate that increasing the airfoil camber leads to delayed LEV initiation and suction breakdown due to higher leading-edge flow curvature. The rate of increase of critical LESP with camber was seen to be independent of Reynolds number. Aftward movement of the maximum camber location was seen to have a reducing effect on the airfoil’s forces and LEV dynamics. Lift and drag forces were observed to be dependent on camber magnitude and location prior to LEV formation but independent during the LEV-dominated part of the motion. The findings from the current work provide insights into reducing the dependency of the LESP on airfoil geometry.
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Data Availability Statement
All data that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
The author gratefully acknowledges Dr. Jack Edwards of North Carolina State University (NCSU) for the REACTMB-INS code used for the computations in this effort. The author would also like to thank Hariharan Ramanathan of NCSU for generating the grids used in the current study.
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Published In
Journal of Aerospace Engineering
Volume 37 • Issue 5 • September 2024
Copyright
© 2024 American Society of Civil Engineers.
History
Received: Apr 23, 2023
Accepted: Apr 11, 2024
Published online: Jul 11, 2024
Published in print: Sep 1, 2024
Discussion open until: Dec 11, 2024
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