Effect of Step Depth and Angle on the Aerodynamics of a Sliding Morphing Skin
American Journal of Aerospace Engineering
Volume 3, Issue 3, December 2016, Pages: 24-30
Received: Sep. 19, 2016;
Accepted: Sep. 27, 2016;
Published: Oct. 18, 2016
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Fadi Mishriky, Department of Aerospace Engineering, Ryerson University, Toronto, Canada
Paul Walsh, Department of Aerospace Engineering, Ryerson University, Toronto, Canada
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The past two decades have witnessed a growing interest among aerospace researchers and designers in aircraft morphing technology. A single aircraft with morphing wings can perform near optimum at different flight regimes by changing the geometry of its wings. With the advancements achieved in this field, a need for a reliable morphing skin is emerging. The demanding task of designing a morphing skin has to compromise between flexibility to ensure low actuation requirements, and high stiffness to carry all the aerodynamic loads. One of the viable designs that fulfills the mechanical requirements is the segmented sliding skin. In such a design, discrete panels overlap to cover the surface of the wing and slide against each other during the morphing motion. From the aerodynamic perspective, the sliding panels introduce backward-facing steps on airfoil surface. In the process of determining the optimum panels’ thickness, this paper presents a comprehensive numerical study on the effect of the step depth and angle on the aerodynamics of an airfoil with a backward-facing step employed on its lower surface. Results showed a significant improvement in the lifting capabilities of the stepped airfoil, and this improvement is directly proportional to the step depth. On the other hand, the separated flow at the step edge induced a low pressure recirculation zone that created a suction force directly proportional to the effective area of the backward-facing step. This resulted in a drag coefficient value that is directly proportional to the step depth. The aerodynamic efficiency of the stepped airfoil was degraded in terms of the lift-to-drag ratio, however decreasing the step depth largely mitigated these adverse effects. Studying different step angles showed that the step can be tilted over a wide range of angles with a negligible effect on the aerodynamics of the stepped airfoil.
Aerodynamics, Backward-Facing Step, Stepped Airfoil, Morphing Wing, Morphing Skin, Segmented Sliding Skin, Computational Fluid Dynamics
To cite this article
Effect of Step Depth and Angle on the Aerodynamics of a Sliding Morphing Skin, American Journal of Aerospace Engineering.
Vol. 3, No. 3,
2016, pp. 24-30.
Copyright © 2016 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/
) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
A. Wickenheiser, and E. Garcia. Aerodynamic modeling of morphing wings using an extended lifting-line analysis. Journal of Aircraft. 2007 Jan;44(1):10-6.
A. Wickenheiser, E. Garcia, and M. Waszak. Evaluation of bio-inspired morphing concepts with regard to aircraft dynamics and performance. In Smart Structures and Materials 2004 Jul 26 (pp. 202-211).
A. Y. Sofla, S. A. Meguid, K. T. Tan, and W. K. Yeo. Shape morphing of aircraft wing: status and challenges. Materials & Design. 2010 Mar 31;31(3):1284-92.
G. Reich, and B. Sanders. Introduction to morphing aircraft research. J Aircraft 2007;44:1059.
M. T. Kikuta. Mechanical properties of candidate materials for morphing wings, 2003, p 123, Department of Mechanical Engineering, Virginia Polytechnic Institute and State University.
C. Thill, J. Etches, I. Bond, K. Potter, and P. Weaver. Morphing skins. The Aeronautical Journal 2008, 112(1129), 117-139.
D. S. Ramrakhyani, G. A. Lesieutre, M. I. Frecker, and S. Bharti. Aircraft structural morphing using tendon-actuated compliant cellular trusses. Journal of aircraft. 2005 Nov;42(6):1614-20.
G. Xijuan, Z. Qiang, and F. Xi. Design Segmented Stiff Skin for a Morphing Wing. Journal of Aircraft. 2015 Dec 22:1-9.
F. Mishriky, and P. Walsh. Effect of the Backward-Facing Step Location on the Aerodynamics of a Morphing Wing. Aerospace 2016, 3, 25.
R. B. Langtry, and F. R. Menter. Correlation-based transition modeling for unstructured parallelized computational fluid dynamics codes. AIAA journal. 2009 Dec; 47(12):2894-906.
F. R. Menter, R. Langtry, and S. Völker. Transition modelling for general purpose CFD codes. Flow, turbulence and combustion. 2006 Nov 1;77(1-4):277-303.
R. B. Langtry, and F. Menter. Transition modeling for general CFD applications in aeronautics. AIAA paper. 2005 Jan 10;522(2005):14.
I. H. Abbott, and A. E. Von Doenhoff. Theory of wing sections, including a summary of airfoil data. Courier Corporation, 1959.