Topology optimization of large-scale 3d morphing wing structures

Abstract

This work proposes a systematic topology optimization approach for simultaneously de-signing the morphing functionality and actuation in three-dimensional wing structures. The actuation was modeled by a linear-strain-based expansion in the actuation material. A three-phase material model was employed to represent structural and actuating materials and voids. To ensure both structural stiffness with respect to aerodynamic loading and morphing capabilities, the optimization problem was formulated to minimize structural compliance, while the morphing functionality was enforced by constraining a morphing error between the actual and target wing shape. Moreover, a feature-mapping approach was utilized to constrain and simplify the actuator geometries. A trailing edge wing section was designed to validate the proposed optimization approach. Numerical results demonstrated that three-dimensional optimized wing sections utilize a more advanced structural layout to enhance structural performance while keeping the morphing functionality better than two-dimensional wing ribs. The work presents the first step towards the systematic design of three-dimensional morphing wing sections.