面向可变体飞行器的仿生植物智能结构非线性多尺度计算及优化方法

Morphing aircrafts can alter their shapes to achieve optimal aerodynamic performance under different flight conditions, of which emergence and development is one of the most important trends of future aircrafts. The shape adaptive structures based on the bioinspired smart materials can provide a balanced stroke, bandwidth and high energy density, and have the properties of actuating, morphing, loading, sensing etc, which provides a new technological approach to morphing aircraft design. Most of Current studies are focused on the design and simulation method for the closed liquid unit cell as well as those simple assembled structures composed of a few cells. The overall objective of this project is to develop a nonlinear multiscale algorithm for the simultaneous design and optimization of the biomimetic adaptive flexible structures and to explore new smart material based compact actuators. Firstly, a new nonlinear multiscale algorithm will be developed based on the multiscale finite element method and co-rotational theories to simulate the pressure adaptive porous materials which composed of unstructured closed liquid motors cells. Subsequently, based on the structural topology optimization method, a nonlinear multiscale optimization method will be developed for the bio-inspired smart materials and structures actuated by the fluid pressure inside in the motor cells. Consequently, combined with the actuation models, such as the ion transport models of the membranes, a novel shape control optimization method with aim on control precision and cost will be developed for the bioinspired smart wings under different flight conditions. Finally, the computation codes will be produced based on the nonlinear multiscale simulation and optimization algorithms proposed. And some experiments about the bio-inspired smart wings will be carried out to validate these proposed methods. It will contribute to the development of morphing aircraft technology and its researches.

可变体飞行器是国家未来飞行器发展的重要方向之一。基于植物运动仿生智能材料与结构能提供较均衡的作动力和较大的作动位移，为可变体飞行器研究设计提供了新的思路。现阶段的研究侧重于对规则含液作动胞元及其简单原型结构分析设计，缺乏解决针对非结构化含液胞元及其跨尺度智能结构的有效数值模拟及优化方法。本项目拟开展仿生植物智能结构的非线性多尺度模拟及优化设计方法研究。首先研究基于非结构化含液胞元压力自适应蜂窝结构作动与承载一体化行为分析的非线性多尺度有限元模型；发展该智能材料与结构在胞元液压作用下多尺度优化方法，实现仿生植物智能结构的宏微观两尺度并行设计；基于细胞膜离子传输等液压生成模型，发展不同飞行条件下以精度和成本等为目标的仿生机翼结构形状优化方法研究。最后开发高效稳定的通用分析软件，进行仿生机翼结构实例模拟并与实验结果对比分析完善算法与软件，为发展新型仿生智能结构尤其是可变体飞行器技术提供科学依据。

可变体飞行器是国家未来飞行器发展的重要方向之一。基于植物运动仿生智能材料与结构能提供较均衡的作动力和较大的作动位移，为可变体飞行器的设计提供了新的技术途径。本项目围绕智能可变形机翼研制过程中材料与结构的多场耦合非线性多尺度等方面问题，研究基于非结构化含液胞元压力自适应蜂窝结构作动与承载一体化行为分析的非线性多尺度有限元模型；发展该智能材料与结构在胞元液压作用下多尺度优化理论，实现其仿生智能结构的微观材料和宏观结构的并行设计；发展不同飞行条件下以精度和成本等为目标的仿生机翼结构形状优化方法研究。此外针对可变形机翼结构设计领域面临的多场耦合基础问题，开展了新型多场耦合数值分析研究，初步提出了单元微分法以及自由单元方法，并对压电结构力电耦合等及其在变形机翼上应用问题进行了分析研究，论证了该方法的有效性。最后，在理论的基础上，本项目开发高效稳定的非线性多尺度有限元分析和新型单元微分法分析软件。.项目执行期间共发表学术论文12篇，其中SCI收录10篇。项目成员积极开展国际交流和合作，赴新加坡，美国参加国际会议3次，国内会议7次，团队成员做学术报告7次，包括项目负责人作会议邀请报告1次。申请软件著作权2项，专利6项。执行期间项目负责人获得军委科技委优胜奖1次，以及2020第三届增材制造全球创新应用大赛“航空航天”竞赛单元金奖1次；此外，协助培养博士毕业生3人，培养毕业硕士生3人，在读博士生2人，在读硕士生5人.培养的研究生获得学校优秀毕业生论文等荣誉。本项目的研究成果为可变形机翼设计过程中所面临的非线性以及多尺度力学分析问题，提供了理论基础，同时为可变形机翼的工程设计提供了有参加价值的理论依据和指导，在科研成果转化方面具有良好的应用前景。