Topology optimization method for high-aspect-ratio wing considering geometric nonlinearity with bending and torsion controls

The high-aspect-ratio wing, which is widely utilized in aircraft to achieve superior aerodynamic efficiency, frequently experiences large deformations such as bending and torsion during its service life. This work focuses on the topology optimization of the high-aspect-ratio wing using multiple materials with bending and torsion controls considering geometric nonlinearity. A novel approach is proposed for achieving a spar-ribs material layout by independently controlling the directional maximum length scale of the void phase. The bending control based on the wing-tip nodal displacement and torsion control based on the deformation difference of the wing-tip nodes are proposed, respectively. Afterwards, the optimization formulations are given and the sensitivity analysis of the optimization responses is derived based on the increment of nodal displacement. The optimized results reveal that the spar-ribs structural layout is successfully attained through directional length scale control. Moreover, the optimized configurations with bending and torsion precisely controlled can be achieved. It also has been demonstrated that considering bending and torsion controls is highly profitable when assessing the trade-off between end compliance in wing optimization.