基于频率加权的后缘拍动变体机翼流场模态分解  

Frequency-weighted dynamic mode decomposition for trailing edge flapping airfoil flow

作　　者：张伟[1,2] 聂旭涛[2] 欧李苇[2] 夏智勋 陈磊[1] ZHANG Wei;NIE Xutao;OU Liwei;XIA Zhixun;CHEN Lei(College of Aerospace Science and Engineer,National University of Defense Technology,Changsha 410073,China;China Aerodynamics Research and Development Center,Mianyang 621000,China)

机构地区：[1]国防科技大学空天科学学院,长沙410073 [2]中国空气动力研究与发展中心,绵阳621000

出　　处：《航空学报》2024年第18期63-78,共16页Acta Aeronautica et Astronautica Sinica

基　　金：国家自然科学基金(52305518)。

摘　　要：变体机翼是提高飞行器机动性能、高升低阻,满足复杂多变工况的重要解决途径之一,探索机翼变形对流场的影响机制是变形控制的基础。针对后缘拍动的柔性变体机翼,为准确分析拍动影响机制,提出了频率加权排序的动力学模态分解方法。针对不同工况下数值模拟结果或试验数据,开展了频率加权法同常规初始值、模态范数排序方法的对比。结果显示频率加权法得到的2阶模态频率与拍动频率吻合,表明该方法能准确体现机翼后缘周期性拍动对流场结构影响,反映机翼变形对尾迹的破碎作用。在相同重构模态数量下,拍动频率为300.0 Hz时,基于数值模拟数据,频率加权法、初始值法、模态范数法重构的速度场误差分别为0.39%、0.58%、3.25%,基于粒子图像测速设备(PIV)试验数据的误差分别为7.56%、8.77%、10.56%,表明频率加权法误差最小,能较好用于主动拍动变体机翼的物理场分析及后续反馈控制。Morphing airfoil is one of the essential solutions to improving the aircraft maneuverability performance, high lift and low drag, and to meeting variable flight conditions. Exploring the mechanism of the wing deformation influence on the flow is the precondition of control. A frequency-weighted ordering approach of dynamic mode decomposition is proposed to analyze the influence mechanism of trailing-edge flapping of a morphing airfoil. The frequency-weighted method is compared with conventional ones, such as the initial value method and the norm method, in terms of the numerical simulation results and experimental data under different working conditions. The second modal frequencies obtained by the frequency-weighted method match the flapping frequencies, indicating its ability to reveal the influence of the periodical flapping on the inner flow structure and wake. Based on the numerical simulation data, with the same number of reconstructed modes and a flapping frequency of 300. 0 Hz, the errors of the frequency-weighted, initial value, and norm methods are 0. 39%, 0. 58%, and 3. 25%, respectively. Based on the PIV test data, the errors become 7. 56%, 8. 77%, and 10. 56%. The frequency-weighted method has the smallest error and can be better used for the flow analysis and subsequent feedback control of active flapping morphing wings.

关 键 词：变体机翼 动力学模态分解 频率加权 拍动 重构 

分 类 号：V224[航空宇航科学与技术—飞行器设计]