Control of Flow Around an Airfoil Using Piezo-Ceramic Actuators

Title & Authors
Control of Flow Around an Airfoil Using Piezo-Ceramic Actuators
Choi, Jin; Jeon, Woo-Pyung; Choi, Hae-Cheon;

Abstract
The objective of this study is to increase lift and decrease drag of an airfoil at high angles of attack by delaying flow separation with piezo-ceramic actuators. The airfoil used is NACA 0012 and its chord length is 0.3m. An experiment is performed at the freestream velocity of 15m/s at which the Reynolds number based on the chord length is $\small{2{\times}10^5}$. Seven rectangular actuators are attached to the airfoil surface and move up and down based on the electric signal. Drag and lift are measured using an in-house two-dimensional force-balance and the surface pressures are also measured. At the attack angle of $\small{16^{\circ}}$, the separation point is delayed downstream due to momentum addition induced by the movement of the actuators. Lift is increased by 10%, drag is reduced by 37%, and the efficiency is increased up to 170%. The flow fields with and without control are visualized using the smoke-wire and tuft techniques.
Keywords
Piezo-Ceramic Actuator;Airfoil;Lift;Drag;Figure of Merit;
Language
Korean
Cited by
References
1.
Gad-el-Hak, M., 1990, 'Control of Low-Speed Airfoil Aerodynamics,' AIAA Journal, Vol. 28, No.9, pp. 1537-1552

2.
Wygnanski, I., 1997, 'Boundary Layer and Flow Control by Periodic Additioin of Momentum,' AIAA Paper 97-2117

3.
Seifert, A., Darabi, A., and Wygnanski, I., 1996, 'Delay of Airfoil Stall by Periodic Excitation,' Journal of Aircraft, Vol. 33, No.4, pp, 691-698

4.
Smith, D., Amitay, M., Kibens, V., Parekh, D., and Glezer, A., 1998, 'Modification of Lifting Body Aerodynamics Using Synthetic Jet Actuators,' AIAA Paper 98-0209

5.
Seifert, A., Eliahu, S., Greenblatt, D., and Wygnanski, I., 1998, 'Use of Piezo Actuators for Airfoil Separation Control,' AIAA Journal, Vol. 36, No.8, pp. 1535-1537