The complex aerodynamic footprint of desert locusts revealed by large-volume tomographic particle image velocimetry.
The complex aerodynamic footprint of desert locusts revealed by large-volume tomographic particle image velocimetry.
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DOI：
10.1098/rsif.2015.0119
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发表时间：
2015-07-06
期刊：
影响因子：
--
通讯作者：
Bomphrey RJ
中科院分区：
文献类型：
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作者：
Henningsson P;Michaelis D;Nakata T;Schanz D;Geisler R;Schröder A;Bomphrey RJ
十多年来，粒子图像测速技术一直是研究动物飞行空气动力学的首选实验技术。在那个时候，硬件变得更容易获得，软件已经从通过流场获取平面发展到重建小体积测量。到目前为止，还不可能捕捉到在一个完整的翼拍周期中留下的空气动力学轨迹的全波长的大体积。在这里，我们使用一种独特的仪器来获得飞行动物整个翼拍的第一个瞬时尾流体积。我们证实了沙漠蝗虫身后尾迹变形的存在，并量化了这种变形对空气动力和升力产生效率的估计的影响。我们提出了先前描述的涡尾迹现象，包括翼尖涡周围的夹带涡，这些涡是由扑翼后剪切层中的开尔文-亥姆霍兹不稳定性产生的一组次级涡。
Particle image velocimetry has been the preferred experimental technique with which to study the aerodynamics of animal flight for over a decade. In that time, hardware has become more accessible and the software has progressed from the acquisition of planes through the flow field to the reconstruction of small volumetric measurements. Until now, it has not been possible to capture large volumes that incorporate the full wavelength of the aerodynamic track left behind during a complete wingbeat cycle. Here, we use a unique apparatus to acquire the first instantaneous wake volume of a flying animal's entire wingbeat. We confirm the presence of wake deformation behind desert locusts and quantify the effect of that deformation on estimates of aerodynamic force and the efficiency of lift generation. We present previously undescribed vortex wake phenomena, including entrainment around the wing-tip vortices of a set of secondary vortices borne of Kelvin–Helmholtz instability in the shear layer behind the flapping wings.