Noda Ryusuke, Nakata Toshiyuki, Liu Hao
Department of Mechanical Engineering, Tokyo University of Technology, 1404-1 Katakura-cho, Hachioji 192-0982, Japan.
Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
Biomimetics (Basel). 2023 Dec 1;8(8):578. doi: 10.3390/biomimetics8080578.
Insects are able to fly stably in the complex environment of the various gusts that occur in nature. In addition, many insects suffer wing damage in their lives, but many species of insects are capable of flying without their hindwings. Here, we evaluated the effect of hindwings on aerodynamics using a Navier-Stokes-based numerical model, and then the passive dynamic stability was evaluated by coupling the equation of motion in three degrees of freedom with the aerodynamic forces estimated by the CFD solver under large and small perturbation conditions. In terms of aerodynamic effects, the presence of the hindwings slightly reduces the efficiency for lift generation but enhances the partial LEV circulation and increases the downwash around the wing root. In terms of thrust, increasing the wing area around the hindwing region increases the thrust, and the relationship is almost proportional at the cycle-averaged value. The passive dynamic stability was not clearly affected by the presence of the hindwings, but the stability was slightly improved depending on the perturbation direction. These results may be useful for the integrated design of wing geometry and flight control systems in the development of flapping-winged micro air vehicles.
昆虫能够在自然界中出现的各种阵风的复杂环境中稳定飞行。此外,许多昆虫在其生命过程中会遭受翅膀损伤,但许多昆虫种类在没有后翅的情况下仍能飞行。在此,我们使用基于纳维-斯托克斯方程的数值模型评估了后翅对空气动力学的影响,然后通过将三自由度运动方程与在大扰动和小扰动条件下由计算流体力学求解器估计的气动力相耦合,评估了被动动态稳定性。在空气动力学效应方面,后翅的存在略微降低了升力产生的效率,但增强了部分前缘涡环流,并增加了翼根周围的下洗流。在推力方面,增加后翅区域周围的机翼面积会增加推力,并且在周期平均值方面这种关系几乎是成比例的。后翅的存在对被动动态稳定性没有明显影响,但稳定性会根据扰动方向略有改善。这些结果可能有助于在扑翼微型飞行器的开发中进行机翼几何形状和飞行控制系统的综合设计。