Unsteady plasma vortex generators for flow separation control of an A-pillar shape bluff body

The aerodynamic drag accounts for more than 20% of the total energy loss of heavy-duty vehicles and around 20% is induced by the tractor at zero degrees yaw angle. One of the contributions comes from the flow separated at the A-pillars (front corners) of the tractor. The aerodynamic design of these corners has improved during the last decades, however, the side winds have a significant detrimental effect on the drag and a real heavy-duty vehicle will be mainly subjected to varying yaw angles. To investigate this point, a bluff body with a square-back and round corners on the leading edges has been chosen as a generic geometry. Our geometry has the flexibility to study separation on different front and back designs and yaw effects (side winds) to demonstrate the potential of unsteady plasma vortex generators (VGs). The effect of the excitation amplitude and duty-cycle parameters on the evolution of the starting vortex by means of Dielectric Barrier Discharge (DBD) VGs has previously been studied; however, there is still a lack of studies exploring its advantage in complex flow-control configurations such as the A-pillar. Particle Image Velocity measurements will detail the dynamics of the unsteady actuation for separation control at different configurations.