仿蝠鲼胸鳍柔性摆动推进流固耦合特性研究

The advantage of higher propulsion efficiency, smaller flow disturbance，and stronger mobility was validated compared bionic propulsion with the traditional propulsion methods (like propeller or jet pump), which pushed the new propulsion model forward. At present, the propulsion mechanism has been revealed, however, the research on propulsion mechanism of coupled flexible locomotion along stretch and chord length like Manta rays swimming with pectoral fins has not been carried out, and the coupled fluid-structure characteristics of active and passive.flexible deformation has not been excavated deeply. This proposal is aimed to promoted the bionic pectoral fins propulsion technology forward. The characteristics of locomotion of swing along the stretch and wave along the chord was obtained by distilled the experimental swatches of flexible pectoral swing locomotion. Based on the characteristics of locomotion along the stretch, the kinematics model was built. The simulation methods of flexible locomotion along stretch and chord length and coupled fluid-structure have been built, and the propulsion mechanism has been revealed. The design method of flexible locomotion of propulsion efficiency and the control mechanism of vortex have been proposed and validated obviously by bionic propulsion experiment. The research findings of this project establish the theoretical basis for developing the bionic pectoral =fin and engineering application.

水下仿鱼类游动推进相比于传统推进方式（螺旋桨/泵喷射）具有推进效率高、水体扰动小、机动性强等优势，已成为未来水下新型推进的重要发展方向。现有研究水下仿鱼类推进侧重于单纯模拟鱼尾拍动，而对于仿蝠鲼类胸鳍推进模式存在的展向摆动与弦向波动耦合推进机理尚未揭示清楚，对于展弦向主被动柔性大变形的流固耦合特性的认识尚待提高。本项目以推动仿胸鳍推进技术发展为目标，提取仿鲼类柔性胸鳍摆动的实验观测样本，建立柔性胸鳍展弦向耦合运动的数学描述模型和主被动耦合形变流固耦合计算方法，掌握柔性胸鳍摆动推进流固耦合特性，并进行试验验证，为仿蝠鲼胸鳍推进技术提升及应用奠定理论基础。

本项目基于蝠鲼类生物游动的实验观测，建立了仿胸鳍运动数学模型，并以此为基础建立了仿蝠鲼柔性胸鳍摆动推进的流固耦合计算方法，通过搭建试验平台，完成了仿蝠鲼柔性胸鳍摆动水池拖曳试验及方法验证，掌握了柔性胸鳍主被动变形对推进性能影响，形成了较为成熟的数值计算与试验方法，为开展水下仿生柔性体流固耦合计算与试验测试提供了新的途径，也初步填补了国内在水下仿生柔性体流固耦合研究手段的空缺。