Interactions Between the Leading Edge Vortex and Sweeping Jet Actuators on a Simple Swept Wing

Abstract

Highly three-dimensional vortical structures and flow separation phenomena present on swept back wings result in complex lift, drag, and pitching moment characteristics. While this may create challenges in the traditional aircraft design process, it provides a promising platform for integrating active flow control (AFC). Subsonic wind tunnel investigations are performed on a highly configurable swept wing model equipped with a spanwise array of sweeping jet actuators at 80% chord. Relating force balance measurements and surface tuft visualizations shed light on how oscillatory blowing interacts with various flow structures over a wide range of geometric and actuator configurations. We show that the lift-enhancing capabilities of AFC is closely related to the strength of vortex lift. We also demonstrate that the unstable pitch behavior of highly swept wings can be mitigated through AFC, significantly extending the flight regime over which the aircraft is trimmed. The optimal actuator distribution depends on the control objective and type of flow conditions present. Detailed understanding of these flow interaction mechanisms will be crucial for effective utilization of AFC technology on future swept wing aircraft.