Actuation System for Effective Flow Control of an Internally Blown Coanda Flap

Abstract

The focus of the work is on the evaluation, development and integration of a robust actuator system for three-dimensional flow control of a blown Coanda flap to improve the high lift system of commercial aircraft. As part of the research work presented, the system is integrated into a wind tunnel model in order to demonstrate its functionality under aerodynamic loads. The system is based on individual bending transducers that can vary the height of the blowing slot dynamically. There are 33 actuated segments to implement static and dynamic actuation along the wing span (3D-actuation). All segments can be controlled independently and thus offer great optimization potential for an effective flow control. The first aerodynamic results show an increase in lift of up to ∆Cl = 0.57. These aerodynamic gains are achieved at amplitudes that do not require the lip segments to completely close or open the blowing slot, which shows the advantage of the current lip design that enables activation with independently controlled stationary and unsteady components.