A strategy for density-based topology optimization of fluid-structure interaction problems is proposed that deals with some shortcomings associated to non stiffness-based design. The goal is to improve the passive aerodynamic shape adaptation of highly compliant airfoils at multiple operating points. A two-step solution process is proposed that decouples global aeroelastic performance goals from the search of a solid-void topology on the structure. In the first step, a reference fully coupled fluid-structure problem is solved without explicitly penalizing non-discreteness in the resulting topology. A regularization step is then performed that solves an inverse design problem, akin to those in compliant mechanism design, which produces a discrete-topology structure with the same response to the fluid loads. Simulations are carried out with the multi-physics suite SU2, which includes Reynolds-averaged Navier-Stokes modeling of the fluid and hyper-elastic material behavior of the geometrically nonlinear structure. Gradient-based optimization is used with the exterior penalty method and a large-scale quasi-Newton unconstrained optimizer. Coupled aerostructural sensitivities are obtained via an algorithmic differentiation based coupled discrete adjoint solver. Numerical examples on a compliant aerofoil with performance objectives at two Mach numbers are presented.

提出了一种基于密度的流固耦合问题拓扑优化策略，该策略解决了与基于非刚度的设计相关的一些缺点。目标是在多个工作点上改善高度柔顺型机翼的被动空气动力学形状适应性。提出了一个两步的求解过程，该过程将全局气动弹性性能目标与结构上固体空隙拓扑的搜索分离。第一步，解决参考完全耦合的流体结构问题，而无需明确惩罚所得拓扑中的非离散性。然后执行正则化步骤，以解决逆向设计问题，类似于顺应性机构设计中的逆向设计问题，它会产生对流体载荷具有相同响应的离散拓扑结构。使用多物理套件SU2进行仿真，该套件包括Reynolds平均Navier-Stokes建模的几何非线性结构的流体和超弹性材料行为。基于梯度的优化与外部罚分方法和大型拟牛顿无约束优化器一起使用。耦合的航空结构灵敏度是通过基于算法微分的耦合离散伴随求解器获得的。给出了具有两个马赫数性能指标的柔顺翼型的数值示例。耦合的航空结构灵敏度是通过基于算法微分的耦合离散伴随求解器获得的。给出了具有两个马赫数性能指标的柔顺翼型的数值示例。耦合的航空结构灵敏度是通过基于算法微分的耦合离散伴随求解器获得的。给出了具有两个马赫数性能指标的柔顺翼型的数值示例。