Cross Jet Control for Manipulating the Separated Shear Flows Behind the Fence

The separated shear flows developed from the vertical fence was manipulated by using the vortex generator jets located in front of the fence. The experiments were carried out in a circulating water channel and the vertical fence was submerged in the turbulent boundary layer. The Reynolds number based on the height of fence and free stream velocity was 2000. DPIV method was used to measure the instantaneous velocity fields around a vertical fence. The mean properties were calculated using the ensemble average method. The obtained results were compared with uncontrolled fence flow. From the results, we found the vortex jets can alter the upstream flow and change the separation bubble behind the fence. As the jet speed increases, the suppression of separation bubble become stronger and the spanwise variation of separation bubble exists.