Experimental and numerical analysis of humpback whale inspired tubercles on swept wings
Aircraft Engineering and Aerospace Technology
ISSN: 0002-2667
Article publication date: 12 April 2022
Issue publication date: 5 December 2022
Abstract
Purpose
With aims to increase the aerodynamic efficiency of aerodynamic surfaces, study on flow control over these surfaces has gained importance. With the addition of flow control devices such as synthetic jets and vortex generators, the flow characteristics can be modified over the surface and, at the same time, enhance the performance of the body. One such flow control device is the tubercle. Inspired by the humpback whale’s flippers, these leading-edge serrations have improved the aerodynamic efficiency and the lift characteristics of airfoils and wings. This paper aims to discusses in detail the flow physics associated with tubercles and their effect on swept wings.
Design/methodology/approach
This study involves a series of experimental and numerical analyses that have been performed on four different wing configurations, with four different sweep angles corresponding to 0°, 10°, 20° and 30° at a low Reynolds number corresponding to Rec=100,000.
Findings
Results indicate that the effect of tubercles diminishes with an increase in wing sweep. A significant performance enhancement was observed in the stall and post-stall regions. The addition of tubercles led to a smooth post-stall lift characteristic compared to the sudden loss in the lift with regular wings. Among the four different wings under observation, it was found that tubercles were most effective on the 0° configuration (no sweep), showing a 10.8% increment in maximum lift and a 38.5% increase in the average lift generated in the post-stall region. Tubercles were least effective on 30° configuration. Furthermore, with an increase in wing sweep, co-rotating vortices were distinctly observed rather than counter-rotating vortices.
Originality/value
While extensive numerical and experimental studies have been performed on straight wings with tubercles, studies on the tubercle effect on swept wings at low Reynolds number are minimal and mainly experimental in nature. This study uses numerical methods to explore the complex flow physics associated with tubercles and their implementation on swept wings. This study can be used as an introductory study to implement passive flow control devices in the low Reynolds number regime.
Keywords
Acknowledgements
The following work has been funded by the Science and Engineering Research Board (SERB), Government of India, under the Grant No: EMR/2015/000879.
The authors would like to thank their respective institutes for providing their facilities and support to carry out this study.
Citation
Joseph, J., A., S. and Sridhar, S. (2022), "Experimental and numerical analysis of humpback whale inspired tubercles on swept wings", Aircraft Engineering and Aerospace Technology, Vol. 94 No. 10, pp. 1577-1592. https://doi.org/10.1108/AEAT-04-2021-0114
Publisher
:Emerald Publishing Limited
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