Wavelet analysis of the coherent structures in airfoil leading-edge separation control by bionic coverts
Wavelet analysis of the coherent structures in airfoil leading-edge separation control by bionic coverts
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仿生隐蔽控制翼型前缘分离相干结构的小波分析
DOI：
10.1177/09544062221135436
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发表时间：
2022-11
期刊：
影响因子：
--
通讯作者：
Nan Jiang
中科院分区：
文献类型：
--
作者：
Xuan Gong;Xingyu Ma;Ziye Fan;Xin Zhang;Nan Jiang
本文通过风洞实验研究了不同材料和锯齿形状的仿生覆体对前缘分离的控制效果。人工柔性覆羽，生物启发鸟类隐蔽羽毛上翼，是铰接在后缘的NACA 0018翼型在一个恒定的大迎角为15。弦为基础的。雷诺数为1.0 3 105在一般范围内的鸟类飞行的性质和低速固定翼无人驾驶航空器。用多通道热线风速仪测量了尾流中的速度分布。通过对平均速度剖面和均方根速度的比较，我们发现尾缘覆盖物使剪切层厚度减少了0.05弦长。后缘和前缘剪切层的湍流强度分别降低了34%和5%。进一步的小波分析表明，大尺度的涡是相当大的时频谱。suppressed.in基于热线数据集，我们开发了一种新的多维遗传算法来分析剪切层中的特征有序结构，并定量表征大尺度和小尺度流动结构之间的振幅调制。结果，我们发现，由尾翼产生的扰动使前缘和后缘剪切层之间的高频（f = 91.2Hz）相干性从40%增加到70%，从而减少了上翼上的流动分离泡。该present.work表明，人工仿生覆翼具有先进的气流分离控制效果，并显示了飞机和无人驾驶飞行器的潜力。the.engineering
We experimentally investigate leading-edge separation control effect by bionic coverts with various materials and.sawteeth shapes in wind tunnel tests. The artificial flexible coverts, bio-inspired by bird covert feathers on upper wings,.are hinged at the trailing-edge of a NACA 0018 airfoil at a constant high angle-of-attack of 15. The chord-based.Reynolds number is 1.0 3 105 in the generic range of bird flight in nature and low-speed fixed-wing unmanned aerial.vehicles. The velocity profiles in the wake flow are measured by multi-channel hot-wire anemometer. By comparing the.mean velocity profiles and root-mean-square velocities, we find the trailing-edge coverts reduced the thickness of the.shear layers by 0.05 chord length. The turbulence intensity of the trailing- and leading-edge shear layers are reduced.34% and 5%, respectively. Further wavelet analysis reveals that the large sizes of vortices are considerably suppressed.in the time-frequency spectrum. Based on the hot-wire datasets, we develop a novel multi-dimensional genetic.algorithm to analyze the featured ordered structures in the shear layers and quantitatively characterize the amplitude.modulation between the large- and small-scale flow structures. As a result, we find that the coverts-generated.perturbations induce an increase in the high-frequency (f = 91.2 Hz) coherence between the leading- and trailing-edge.shear layers from 40% to 70%, leading to a reduction of the flow separation bubble on the upper wing. The present.work reveals that the artificial bionic coverts have leading-edge flow separation control effectiveness and shows the.engineering potential for aircrafts and unmanned aerial vehicles.
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影响因子：
8.6
作者：
SHE, ZS;LEVEQUE, E
通讯作者：
LEVEQUE, E
仿生羽毛瓣被动控制翼型升力的实验研究
影响因子：
3.4
作者：
王龙军;Alam Md Mahbub;周裕
通讯作者：
周裕
影响因子：
4.6
作者：
Lei Wang;Xiaomin Liu;Dian Li
通讯作者：
Lei Wang;Xiaomin Liu;Dian Li
DOI：
10.1177/09544062211020773
发表时间：
2021-06
期刊：
Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science
影响因子：
--
作者：
Massoud Tatar;M. Masdari;M. Tahani
通讯作者：
Massoud Tatar;M. Masdari;M. Tahani
影响因子：
4.6
作者：
Hasan Kamliya Jawahar;S. A. Showkat Ali;M. Azarpeyvand
通讯作者：
Hasan Kamliya Jawahar;S. A. Showkat Ali;M. Azarpeyvand