Zwerger, C., Hickel, S., Breitsamter, C. Adams, N.A. (2015)
AIAA paper 2015-2572. doi: 10.2514/6.2015-2572

We performed wall-modeled large-eddy simulation of the flow field around the VFE-2 delta wing, focusing on two aspects: (1) leading-edge bluntness effects on the primary vortex separation and (2) vortex breakdown above the wing and its control. Regarding aspect (1), the VFE-2 delta wing with sharp leading-edge (SLE) and medium radius round leading-edge (MRLE) are considered for three angles of attack α = {13°, 18°, 23°} leading to different overall flow characteristics.

The numerical simulations correctly predict the main flow phenomena and are quantitatively in reasonable to good agreement with experi- mental measurements of steady and unsteady surface pressures, velocity distributions, and vortex breakdown position and frequency. Regarding aspect (2), flow control by oscillating control surfaces and flow control by a geometric modification leading to an injection of fluid from the pressure side are investigated for the SLE at α = 28°. Considering the influence on vortex breakdown position, the numerical simulations confirm experimental observations regarding oscillating control surfaces, and show promising potential for flow control.