Numerical prediction of aerodynamic performance for a flying fish during gliding flight
Numerical prediction of aerodynamic performance for a flying fish during gliding flight
复制标题
飞鱼滑翔飞行气动性能数值预测
DOI：
10.1088/1748-3190/ab23e6
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发表时间：
2019-07-01
影响因子：
3.4
通讯作者：
Mao, Xuerui
中科院分区：
文献类型：
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作者：
Deng, Jian;Zhang, Lingxin;Mao, Xuerui
飞鱼是一类独特的空中水生动物，既能在水中游泳，也能在海面上滑行。以前对它们的气动特性的研究大多是基于现场观测或对它们的形态参数的测量。在本研究中，我们考虑了三种不同的飞鱼模型，其中初步的一个模型在胸鳍形态上模仿了Cypselurus hiraii，遵循了先前的风洞实验(Park和Choi 2010 J.Exp.比奥尔。2133269-79)。用计算流体力学(CFD)方法对其气动性能进行了数值研究。当迎角α=35度时，升力系数达到最大值1.03；当迎角α=6度时，升阻比达到最大值4.7。根据俯仰力矩分布的负斜率，通过适当选择重心，证明了飞鱼模型是纵向稳定的。在此基础上，基于仿真得到的气动系数，建立了纵向平面三自由度(3-DOF)的动力学模型，以预测其滑翔性能。结果表明，飞鱼可以达到45.4m的距离，13.2 m的高度，表现出非凡的滑翔性能。数值模拟结果与前人的实验结果和理论预测基本一致，可以作为机器飞鱼进一步研究的基础。
Flying fish is a family of unique aerial-aquatic animals, which can both swim in the water and glide over the sea surface. Most previous studies on their aerodynamic characteristics were based on field observations or measurements of their morphometric parameters. In the present study, we consider three different flying fish models, of which the preliminary one mimics the Cypselurus hiraii in the pectoral fin morphology, following a previous wind tunnel experiment (Park and Choi 2010 J. Exp. Biol. 213 3269-79). Their aerodynamic performances are numerically studied by the computational fluid dynamics (CFD) method. The maximum lift force coefficient of 1.03 is reached at the angle of attack alpha = 35 degrees, and the maximum lift-to-drag ratio of 4.7 is achieved at alpha = 6 degrees. By choosing appropriately the center of gravity, the flying fish model is proved to be longitudinally stable, according to the negative slope of pitching moment profile. Furthermore, we build a three-degrees of-freedom (3-DOF) dynamic model in the longitudinal plane based on the aerodynamic coefficients obtained in our simulations, to predict its gliding performance. The results show that the flying fish can achieve a distance up to 45.4 m, and reach a height of 13.2 m, indicating an extraordinary gliding performance. Our numerical simulations are consistent with previous experimental results and theoretical prediction, which can be taken as the basis of further research on robotic flying fish.