Planform and Flexibility on Lift Characteristics for Flow over Low-Aspect Ratio Wings
Publication: Journal of Aerospace Engineering
Volume 23, Issue 1
Abstract
Force measurement and surface oil flow visualization were carried out in wind tunnel to investigate the effects of wing’s planform and flexibility on aerodynamics for flow over low-aspect ratio wings. It is found that the empirical formulas proposed by Polhamus can present remarkably accurate predictions before stall for both rigid and flexible wings. The spiral vortex is responsible for rigid and flexible wing abrupt drop of lift coefficient after stall when the sweep angle is below 35°. The maximum lift coefficient and the stall angle for flexible wings are smaller than those for rigid ones when the sweep angle is below 40°, and the wing flexibility nearly does not influence the aerodynamics as the sweep angle is beyond 40°. Moreover, lift coefficient curves exist hysteresis loop in the following range of sweep angle: 10°–35° for the flexible wings and 5°–50° for the rigid wings. It can be deduced from oil visualization experiment that the sudden disappearance of spiral vortex flow structure may be responsible for the hysteresis.
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Acknowledgments
This project (Grant No. UNSPECIFIED10425207) is supported by the National Natural Science Foundation of China (NSFC).UNSPECIFIED
References
Gordnier, R. E., and Visbal, M. R. (2005). “Compact difference scheme applied to simulation of low sweep delta wing flow.” AIAA J., 43(8), 1744–1752.
Gursul, I. (2004). “Recent developments in delta wing aeridynamics.” Aeronaut. J., 108(1087), 434–452.
Kulfan, R M. (1979). “Wing geometry effects on leading edge vortices.” Rep. No. AIAA-78-1872, 1–37.
Liu, Z. Z., Liu, M. J., and Su, W. H. (1982). “Pressure measurement, surface oil flow visualization and analysis of lift enhancement for strake wing at high attack angle and low speed.” Rep. Prepared for BUAA, Institute of Fluid Mechanics, 1–10 (in Chinese).
Lu, S. F. (2005). “Experimental investigation on the vortex structures and aerodynamics for flow over 50-deg sweep delta wings.” Graduate dissertation, School of Aeronautic Science and Engineering, Beijing (in Chinese).
Mueller, T. J., and Delaurier, J. D. (2003). “Aerodynamics of small vehicles.” Annu. Rev. Fluid Mech., 35, 89–111.
Pelletier, A., and Mueller, T. J. (2000). “Low Reynolds number aerodynamics of low-aspect-ratio, thin/flat/cambered-plate wings.” J. Aircr., 37(5), 825–832.
Polhamus, E. C. (1966). “A concept of the vortex lift of sharp-edge delta wings based on a leading-edge-suction analogy.” Rep. No. NASA TN D-3767, 1–15.
Polhamus, E. C. (1971). “Predictions of vortex-lift characteristics by a leading-edge-suction analogy.” J. Aircr., 8(4), 193–199.
Su, W. H., Liu, M. J., and Liu, Z. Z. (1989). “Separated flow types and boundaries of plane delta wing with sharp edges.” Rep. No. BH-B3483, Beijing Univ. of Aeronautics and Astronautics, 1–20 (in Chinese).
Taylor, G. S., Korker, A., and Gursul, I. (2005). “Passive flow control over flexible non-slender delta wings.” Rep. No. AIAA-2005-0865, 1–17.
Taylor, G. S., Schnorbus, T., and Gursul, I. (2003). “An investigation of vortex flows over low sweep delta wings.” Rep. No. AIAA-2003-4021, 1–13
Torres, G. E., and Mueller, T. J. (2004). “Low-aspect-ratio wing aerodynamics at low Reynolds numbers.” AIAA J., 42(5), 865–873.
Wang, J. J., and Liu, Y. (2008). “Experimental study on lift characteristics for flow over flexible cropped delta wings.” J. Aircr., 45(6), 2158–2161.
Wang, J. J., and Tu, J. Q. (2007). “The effects of planform on aerodynamic of MAV.” Acta Aerodynamica Sinica, 25(4), 474–478 (in Chinese).
Wang, J. J., and Wu, K. (2007). “Experimental investigations of the effect of wing elastic deformations on aerodynamics.” Acta Aerodynamica Sinica, 25(1), 55–59 (in Chinese).
Wang, J. J., and Zhang, W. (2008). “Experimental investigations on leading-edge vortex structures for flow over non-slender delta wings.” Chin. Phys. Lett., 25(7), 2550–2553.
Wang, J. J., Zhao, X., Liu, W. C., and Tu, J. Q. (2007). “Experimental investigation on flow structures over nonslender delta wings at low Reynolds numbers.” J. Experimental Fluid Mechanics, 21(2), 1–7.
Wu, K. (2005). “The effect of flexibility on aerodynamics of 40-deg sweep cropped delta wings.” Graduate dissertation, School of Aeronautic Science and Engineering, Beijing (in Chinese).
Information & Authors
Information
Published In
Journal of Aerospace Engineering
Volume 23 • Issue 1 • January 2010
Pages: 55 - 61
Copyright
© 2010 ASCE.
History
Received: May 15, 2008
Accepted: Apr 10, 2009
Published online: Dec 15, 2009
Published in print: Jan 2010
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