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 Research  Interests   

- Flow control around a circular cylinder with a porous ring at Re=30000: vorticity fields for the control-off (up) and the porous  (down) cases. A tremendous regularized flow is obtained with the passive control as the flow changes from a chaotic distribution of vortices to a regular Karman street behind the cylinder (Bruneau & Mortazavi JOPE 06). Direct numerical simulations are performed using a multigrid/penalization code.

without control
      Without control

with control
      With control

- Passive control around a square back Ahmed body on the top of a road
at Re=30000 with a porous layer in the upper side of the obstacle (direct numerical simulations are performed using a multigrid/penalization code):

                          control geometry

Pressure field:

without control
      Without control; average drag coefficient: 0.526

with control
      With control
; average drag coefficient: 0.332 (-33%)

Closed-loop active control with two small pulsed jets implemented on the upper and lower parts of a vertical step in a channel flow (Re=2000). The main target of this control technique is to influence directly the vortex shedding and the main recirculation zone: the upper jet changes the shedding dynamics and the lower one perturbates and pushes away the recirculation zone. Computations are performed using high accuracy vortex methods (Creusé et al. 2007, submitted).

                                                                          Control with oscilating inlet velocities
Sensors for closed-loop control
                                                  Control with synthetic or pulsed jets on the step

   step uncontrolled
         Averaged streamlines for an uncontrolled flow.

   controlled step
Averaged streamlines for a closed-loop controlled flow with pulsed jets on the step walls.