A morphing wing with cellular structure of non-uniform density

Abstract

This paper proposes an optimization design method for the modular cellular structure of non-uniform density, which is filled into the morphing wing to generate variable torsion angle. By actively adjusting the distribution of the span-wise torsion angle, the lift distribution on the wing surface can be properly adjusted to avoid the problem of aeroelastic divergence or reduce the bending moment at the wing root. This ability is validated using CFD simulation. In the optimization framework proposed, the adaptive gradient algorithm is used to suppress the divergence of iteration. A finite element model with geometrical nonlinear effects is then proposed to correct the errors of the linear analysis and verify the effectiveness of the optimization method. This design is shown to be able to reduce the overall weight of the structure and achieve control of the macro mechanical performance of the wing. The work provides a general optimization design method for similar modular structures, allowing independent programmable adjustment of the parameters of each single structural cell.