This work is a numerical investigation on the performance of integrally actuated two-dimensional membrane wings made with dielectric elastomers. A high-fidelity model based on the direct numerical integration of the unsteady Navier-Stokes equations is coupled with a geometrically non-linear structural model. The rate-dependent constitutive law for the dielectric elastomer is based on a non-linear formulation, and it has been validated against experimental data. In addition, the implementation of the aeroelastic framework has been verified against the relevant literature for the low-Reynolds number flows investigated in this dissertation. Numerical simulations of the open-loop dynamics of the actuated membrane, in good agreement with experimental observations, show that integral actuation offers enough authority in the control of the wing aerodynamic performance. Dielectric elastomers can then be used as embedded actuators, coupling the advantages of passive membranes with a simple and lightweight control mechanism. ududFurther, this work also proposes a model-reduction methodology for the fully coupled system to aid control system design. The low-order description of the actuated system can capture the main system dynamics, and can be used for the design of the control scheme of the wing. Proportional-Integral-Derivative and Linear Quadratic Gaussian feedback controllers, designed using the reduced-order model, are finally implemented in the high-fidelity model for the rejection of flow disturbances. Results show that the wing aerodynamic performance is noticeably enhanced through the actuation as the disturbances on the lift in case of gusts can be reduced up to 60%.
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机译：这项工作是对由介电弹性体制成的整体驱动二维膜翼性能的数值研究。基于非稳态Navier-Stokes方程的直接数值积分的高保真模型与几何非线性结构模型耦合。介电弹性体的速率相关本构律基于非线性公式，并且已针对实验数据进行了验证。此外，针对本文研究的低雷诺数流的相关文献，对气动弹性框架的实现进行了验证。与实验观察结果很好地吻合了被驱动膜的开环动力学的数值模拟表明，整体驱动为机翼空气动力性能的控制提供了足够的权限。然后，可以将介电弹性体用作嵌入式致动器，从而将被动膜的优点与简单而轻巧的控制机制结合在一起。 ud ud此外，这项工作还为全耦合系统提出了一种模型简化方法，以帮助控制系统设计。致动系统的低阶描述可以捕获主要系统动力学，并且可以用于机翼控制方案的设计。使用降阶模型设计的比例-积分-微分和线性二次高斯反馈控制器最终在高保真模型中实现，以抑制流动扰动。结果表明，通过操纵，机翼的空气动力学性能得到了显着提高，因为阵风时升力的扰动可以减少多达60％。
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