Effects of pulsed and continuous jet vortex generators in a turbulent boundary layer flow – an investigation by using two high-speed stereo PIV systems

Two high-speed stereo PIV (HS-SPIV) systems have been used for the characterization of pulsed and continuous jet actuators in the turbulent boundary layer (TBL) wind tunnel at ONERA Lille, an Eiffel type wind tunnel in suction mode with a low turbulence level. The test aimed at generating an aerodynamic database useful for the characterisation of (unsteady) vortical structures responsible for the wall-normal fluid exchange which enable an increase of wall-shear stress in the wake of the jet actuator row. Jet vortex generators are well-established for controlling resp. inhibiting flow separation in flows with adverse pressure gradients. Comparing the efficiency of continuous and pulsed jet vortex generators is still of big interest for TBL flows in many aerodynamic and technical flow systems. The dataset is also useful for the validation of CFD tools or simplified models for such flow control devices. The work has been realized in close collaboration between ONERA and DLR.