Experimental Study of Flow Control on Bluff Body using Piezoelectric Actuators

Nabil Tounsi (1) , Rafika Mestiri (2) , Laurent Keirsbulck (3) , Hamid Oualli (1) , Samir Hanchi (1) , Fethi Aloui (3)

1 EMP - École Militaire Polytechnique [Alger]
2 ENIM - École Nationale d’Ingénieurs de Monastir
3 LAMIH - Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines - UMR 8201

Active flow control is experimentally investigated on a car-type bluff body. The actuation is based on a synthetic jet actuator placed at the top of the Ahmed body rear window. In the present paper, a synthetic jet characterization is presented, the frequencies and the optimal amplitudes with regard to the spatial evolution are analyzed. All the measurements are carried out in a wind tunnel at Reynolds numbers based on the body length between 106 and 106. The bluff body shows a maximum drag reduction of 10% when optimal control is applied. Independent effect of the reduced frequency and the momentum coefficient actuation parameters on the drag reduction are also detailed in the present paper. This reduction induces changes in the flow field due to the piezoelectric actuation. The flow topology modification is investigated via particle image velocimetry measurements in order to estimate the flow response to a local excitation and to understand the mechanism involved in the aerodynamic drag control.

Mots clés: Flow control; Drag reduction; Synthetic jet; Bluff body; Piezoelectric actuator

Domaines: Mécanique [physics.med-ph]; Mécanique des fluides [physics.class-ph]

Nabil Tounsi, Rafika Mestiri, Laurent Keirsbulck, Hamid Oualli, Samir Hanchi, et al.. Experimental Study of Flow Control on Bluff Body using Piezoelectric Actuators. Journal of Applied Fluid Mechanics, 2016, 9 (2), pp.827-838. ⟨10.18869/acadpub.jafm.68.225.24488⟩. ⟨hal-03448166⟩