A Lightweight Concept for Aerodynamic Surfaces with Variable Camber

Abstract

In this work new concept for an aerodynamic surface with variable camber is presented. The changes with respect to the traditional structural design are kept to a minimum. The conventional rib, in charge of the aerodynamic section’s shape stability, is replaced by a “camber-flexible” rib. In contrast to the traditional rib, the camber-flexible rib allows in-plane deformations. However, due to the rib’s special construction, these occur mainly as changes in the section camber. The section camber can be selected and controlled under load by an appropriate actuator system. The camber-flexible rib is realized with a closed shell (belt), reinforced by in-plane stiffeners (spokes). The spokes' main task is to restrain the rib’s in-plane flexibility in such a way, that undesired deformations can be avoided. The spokes are connected to the belt by hinges and the whole section stiffness of the rib is provided by the belt’s bending stiffness. Together with the description of the new structure, with some options for the integration in a real aerodynamic surface, some simulation and experimental results on a prototype are presented in the paper.