Numerical Study of Flow Separation Control over a NACA2415 Airfoil

Authors: M. Tahar Bouzaher

Abstract:

This study involves numerical simulation of the flow around a NACA2415 airfoil, with a 18° angle of attack, and flow separation control using a rod, It involves putting a cylindrical rod - upstream of the leading edge- in vertical translation movement in order to accelerate the transition of the boundary layer by interaction between the rod wake and the boundary layer. The viscous, nonstationary flow is simulated using ANSYS FLUENT 13. The rod movement is reproduced using the dynamic mesh technique and an in-house developed UDF (User Define Function). The frequency varies from 75 to 450 Hz and the considered amplitudes are 2%, and 3% of the foil chord. The frequency chosen closed to the frequency of separation. Our results showed a substantial modification in the flow behavior and a maximum drag reduction of 61%.

Keywords: CFD, Flow separation, Active control, Boundary layer, rod, NACA 2415.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1337257

References:

[1] Serdar Genc, M., Hakan, k Acıkel, H. An experimental study on aerodynamics of NACA2415 aerofoil at low Re numbers Journal of Experimental Thermal and Fluid Science: 10.1016.
[2] Mittal R., Kotapati R.B. et Cattafesta L. 2005. "Numerical study of resonant interactions and flow control in a canonical separated flow". AIAA Paper, No. 2005-1261.
[3] Greenblatt D, Wygnanski IJ. The control of flow separation by periodic excitation. Prog Aerospace Sci 2000;36:487–545.
[4] Amotsu Igarashi. (1997) "Drag reduction of a square prism by flow control using a small rod”. Journal of Wind Engineering and Industrial Aerodynamics; 69 71 141-153.
[5] Igarashi, T., Nobuaki, T.Drag reduction of flat plate normal to airstream by flow control using a rod .Journal of Wind Engineering and Industrial Aerodynamics 90 (2002) 359–376.
[6] T.sutsui, Igarashi, T. Drag reduction of a circular cylinder in an airstream Journal of Wind Engineering and Industrial Aerodynamics 90 (2002) 527–541.