Wind Tunnel Comparison of Flapped and FishBAC Camber Variation for Lift Control

Unlike hinged flaps (e.g. ailerons, elevator and rudder), camber morphing devices vary camber distribution in a smooth and continuous way, resulting on aerodynamic efficiency improvements due to the absence of surface discontinuities. One such camber morphing concept, the Fish Bone Active Camber (FishBAC) device, has shown significant aerodynamic benefits when compared to a flap. A 2D wind tunnel tes twas performed to further investigate the FishBAC’s behavior in terms of its aerodynamic performance and the size and structure of the shed wake. To establish a direct comparison, a hinged flap was also tested under equivalent flow conditions. A combination of quasi-steady force balance and wake rake pressure measurements were used to determine aerodynamic force coefficients. Additionally, these measurements are complemented by a flow visualization study performed using Particle Image Velocimetry, where a visual comparison on the size and vortical structure of the near field wakes was conducted. Results show that the FishBAC achieves at least 16% higher aerodynamic efficiency than the flap.