Understanding the Impact of a Serrated Trailing Edge on the Unsteady Hydrodynamic Field
Publication: Journal of Aerospace Engineering
Volume 34, Issue 4
Abstract
Trailing edge noise is a common noise source in aerodynamic applications. Many prior experiments have shown that trailing edge serrations can reduce this noise, but the mechanism by which serrations reduce noise and their aerodynamic impact near the edge is not fully understood. Previous theoretical models have assumed that the turbulence convecting past a serrated trailing edge is unchanged by the presence of the serrations, but experiments have shown that this is not accurate. This work attempts to further the understanding of unsteady surface pressure fluctuations on sawtooth serrations. Experiments were performed in an anechoic wall-jet wind tunnel on an undercut trailing edge with a straight and serrated edge configuration. The magnitude of unsteady surface pressure fluctuations was found to increase near the tips of the serrations for Strouhal numbers near 0.5 based on edge thickness. Spanwise coherence was increased on a single serration, while coherence across the root of adjacent serrations was similar to results across a straight trailing edge at similar spanwise separation distance.
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Data Availability Statement
Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
The authors thank Dr. Matthew Szoke (Virginia Tech) and Dr. Lorna Ayton (University of Cambridge) for their collaborative discussions.
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Published In
Journal of Aerospace Engineering
Volume 34 • Issue 4 • July 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: Dec 8, 2020
Accepted: Mar 5, 2021
Published online: May 13, 2021
Published in print: Jul 1, 2021
Discussion open until: Oct 13, 2021
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