Thiria Benjamin, Godoy-Diana Ramiro
Physique et Mécanique des Milieux Hétérogènes (PMMH), UMR 7636 CNRS, ESPCI ParisTech, UPMC, Université Denis Diderot, Paris, France.
Phys Rev E Stat Nonlin Soft Matter Phys. 2010 Jul;82(1 Pt 2):015303. doi: 10.1103/PhysRevE.82.015303. Epub 2010 Jul 19.
Wing flexibility governs the flying performance of flapping-wing flyers. Here, we use a self-propelled flapping-wing model mounted on a "merry go round" to investigate the effect of wing compliance on the propulsive efficiency of the system. Our measurements show that the elastic nature of the wings can lead not only to a substantial reduction in the consumed power, but also to an increment of the propulsive force. A scaling analysis using a flexible plate model for the wings points out that, for flapping flyers in air, the time-dependent shape of the elastic bending wing is governed by the wing inertia. Based on this prediction, we define the ratio of the inertial forces deforming the wing to the elastic restoring force that limits the deformation as the elastoinertial number N(ei). Our measurements with the self-propelled model confirm that it is the appropriate structural parameter to describe flapping flyers with flexible wings.
翅膀的柔韧性决定了扑翼飞行器的飞行性能。在此，我们使用安装在“旋转木马”上的自推进扑翼模型，来研究翅膀柔韧性对系统推进效率的影响。我们的测量结果表明，翅膀的弹性不仅能大幅降低功耗，还能增加推进力。使用翅膀的柔性板模型进行的比例分析指出，对于在空中扑动的飞行器，弹性弯曲翅膀随时间变化的形状由翅膀惯性决定。基于这一预测，我们将使翅膀变形的惯性力与限制变形的弹性恢复力之比定义为弹性惯性数N(ei)。我们对自推进模型的测量证实，它是描述具有柔性翅膀的扑翼飞行器的合适结构参数。
