悬停飞昆虫拍动翼低雷诺数高升力气动机理研究

采用数值方法对果蝇翼悬停飞行拍动翼问题进行了模拟,介绍了前人生物观察和动态比例模型得来的简化拍动翼运动规律。果蝇翼模型平面形状采用Dickinson动态比例试验采用的形状,计算的无量纲参数根据Weis-Fogh,和Vogel果蝇捆绑飞行的数据得到。分别数值模拟了三种运动模态:超前模式(advanced mode),对称模式(symmetrical mode)和滞后模式(delayed mode)。数值模拟的结果同Dickinson的试验结果和孙茂的数值模拟结果进行了比较,吻合很好,表明本文的计算结果是合理的。根据数值模拟结果,结合气动力系数和流场结构进行分析,研究了果蝇悬停飞行获得高升力的流动机理。

Study of high aerodynamic lift mechanics of hovering insect flapping wing at low Reynolds number

The numerical method was used to simulate the flowfield around the flapping wing of hovering fruit fly.The movement of the simplified flapping wing model,which was obtained through observation by the former and was used in dynamic scaling models experiment,was described.The shape of the fruit fly wing was the same as Dickinson's experiment.And the present CFD dimensionless parameters were got from the tethered experiments of Weis-Fogh and Vogel.Three kinds of flapping mode: advanced mode,symmetrical mode and delayed mode were simulated.And the present CFD results consisted with Dickinson's experiment and Sun's numerical simulation very well.The aerodynamic mechanism of the high lift of the hovering fruit fly flapping wing was studied through analyzing the unsteady aerodynamic coefficients and the structures of the flowfield.