Actuation systems for raised Krueger flaps on laminar airfoils

Laminarization of airfoils offers great potential for improving aerodynamic performance and presents a key aspect of research in the optimization of modern commercial aircraft. Still, a challenge to be faced is potential contamination of the wing’s leading edge, which creates turbulence wedges that prevent maintained laminar flow. The raised bull-nose Krueger flap poses a solution to this by shielding the leading edge and thus protecting the wing from contamination. However, an actuation system fulfilling the requirements resulting from this concept is yet to be developed and proven. The aim of this paper is to present a feasible actuation system concept for these control devices, while indicating challenges and limitations.