Experimental Investigation of Effects of Split Blended Winglet at Tip Vortex Structure of Micro-Aerial Vehicle with Hot-Wire Anemometry

Authors

1 M.S.C., Mech. Eng., Hakim Sabzevari Univ., Sabzevar, Iran

2 Assoc. Prof., Mech. Eng., Hakim Sabzevari Univ., Sabzevar, Iran

3 Mechanical Engineering, Hakim Sabzevari University.

Abstract

Winglets are one of the tools used for reducing the effects of the tip vortex. In this research, the effects of installing split blended winglet on Micro-Aerial Vehicle half model in order to the reduction of wing tip vortex were investigated experimentally. The experiments were conducted in an open circuit wind tunnel at velocity 16 m/s and angle of attack 10ᵒ. The Reynolds number of the model was about 3.8×104 based on Mean-Aerodynamic chord. In order to measure the mean velocity and turbulence intensity, the Hot-Wire Anemometry (HWA) has been used. Experimental results in the absence of installing winglet indicated the existence of a vortex structure behind the tip of the wing which is due to the pressure difference created on the upper and lower surfaces of the wing. Turbulence intensity has it highest value in vortex core which is also observed to decrease gradually with downstream distance. The results show that in the presence of winglet, there are two clear vortex structures which one at the winglet/wing junction and the other at the tip of the winglet.

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References

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Journal of Solid and Fluid Mechanics
Volume 8, Issue 2
July 2018
Pages 193-204

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