一种新型仿生翼型流动机理的探索研究

Bionic morphing wing aircraft has an extremely promising application prospect in the military and civil fields. It becomes a hot research spot at home and abroad. Morphing wing is an important part of bionic morphing aircraft, the airfoil is the key factor in the wing design, so the bionic airfoil will is the key technology in the research of bionic morphing aircraft. The project idea comes from the flying seagulls. The local details of seagull wing are carefully observed, and the seagull wing trailing edge looks like “scissor mouth” shape. So a kind of novel bionic airfoil is presented, namely "scissor mouth" bionic airfoil. The simulation investigation of the novel bionic airfoil is adopted by detached eddy simulation (DES) and the flow mechanism of the novel bionic airfoil will be investigated. The effect of "scissors mouth" configuration on airfoil aerodynamic performance is explored, and the validation of "scissors mouth" control mechanism of flow around airfoil is realized by wind tunnel experiment. The comparison between simulation and experiment is used to explore the new flow mechanism and phenomena, and it will offer the theoretical support for the experimental research and engineering application of "scissors mouth" bionic airfoil.

仿生变体飞行器是一种新概念的飞行器，在军事和民用领域存在广泛应用前景，是目前国内外的研究热点。变形机翼是仿生变体飞行器的重要组成部分，翼型是机翼设计的关键因素，因此仿生翼型将是仿生变体飞行器研究中的关键核心技术。项目的思想来源于飞行中的海鸥翅膀，通过仔细观察海鸥翅膀的局部细节，发现翅膀后缘呈“剪刀口”型，提出了一种经过抽象化后的仿生翼型，即“剪刀口”仿生翼。项目以脱体涡数值模拟方法（DES）为基础，开展新型仿生翼型的数值模拟，重点分析新型仿生翼型绕流的流动机理，讨论“剪刀口”构型对翼型气动特性的影响，探索“剪刀口”对翼型绕流的影响机制，开展风洞实验验证工作。最后通过风洞实验和数值分析的对比分析，力求发现新的流动机理和流动现象，为其更加深入的实验研究及实现该仿生翼的工程应用提供基础理论支撑。

项目的思想来源于飞行中的海鸥翅膀，通过仔细观察海鸥翅膀的局部细节，发现翅膀后缘呈剪刀口型，提出了一种经过抽象化后的仿生翼型，即“剪刀口”仿生翼。项目采用数值模拟和风洞实验相结合的方法研究新型仿生翼型的流动机理，研究结果表明：仿生翼能够改善翼型的失速性能，但是小迎角时需要付出增阻、减升的代价。小片形状、位置及角度是改善仿生翼失速性能的关键几何参数。研究结果证实了鸟类着陆飞行时，打开翅膀上表面羽毛的原因，即形成本项目中的“仿生翼”构型。通过项目的研究，可以为更加深入的实验研究及仿生翼工程应用提供基础理论支撑。