Aerodynamics of Insect Flight In TurbulentFlow

昆虫在湍流中飞行的空气动力学

• 批准号: 284179552
• 负责人: Professor Dr. Fritz-Olaf Lehmann
• 金额: --
• 依托单位: Centre de Mathématiques et dInformatique
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/284179552?language=en
• 关键词: Aerodynamics; Insect; Flight; TurbulentFlow

The aerodynamics of insect flight currently receives high attention. The fundamentals of insect flight were first explored assuming that insects move in quiescent air. However, natural environment is typically turbulent, but we know very little on how insects manage to fly on windy days. For man-made micro air vehicles it is likewise important to fly under difficult flow conditions. This project proposes to investigate the interaction of insects with turbulence from complementary perspectives of experimental biology and computational fluid dynamics. We will define a set of model turbulent flows with reproducible statistical properties, varying systematically the energy content of the scales of turbulent motion, with similar flow conditions in experiments and numerical simulations. We also put a major emphasis on the significance of wing elasticity, and devise a suitable flexible wing model that closely mimics the elastic properties of real wings, which we measure in an experimental facility. Biological experiments account for the whole complexity of animals, including the brain, sensory system and the resulting changes in the wing-beat kinematics under perturbed flight conditions. Numerical simulations allow studying isolated effects and thus to reduce the problem's complexity. We combine biological experiments on tethered and freely flying insects on the one hand, and numerical simulations of model insects with rigid and flexible wings in tethered and free flight in a similar turbulent flow environment on the other hand. This allows giving at least partial answers to the three major questions we consider: (i) What are impacts, benefits and limitations of environmental turbulence on the aerodynamics of flapping insect flight? (ii) How does turbulence affect the energetic cost of flapping flight with flexible and rigid wings? (iii) What behavioral strategies do insects employ to cope with turbulent perturbations? These questions are relevant for both fundamental and applied research, and their interdisciplinary nature requires employing several perspectives.

昆虫飞行的空气动力学目前受到高度重视。首先探讨了昆虫飞行的基本原理，假设昆虫在静止的空气中运动。然而，自然环境通常是动荡的，但我们对昆虫如何在刮风的日子里飞行知之甚少。对于人造微型飞行器来说，在困难的流动条件下飞行同样重要。该项目建议从实验生物学和计算流体力学的互补角度来研究昆虫与湍流的相互作用。我们将在实验和数值模拟中定义一组具有可重复统计特性的湍流模型，系统地改变湍流运动尺度的能量含量，并具有相似的流动条件。我们还着重强调了机翼弹性的重要性，并设计了一个合适的柔性机翼模型，该模型接近于真实机翼的弹性特性，我们在实验装置上进行了测量。生物实验解释了动物的整个复杂性，包括大脑、感觉系统以及在扰动飞行条件下翅膀拍打运动学的结果变化。数值模拟可以研究孤立效应，从而降低问题的复杂性。我们一方面对被拴住和自由飞行的昆虫进行了生物学实验，另一方面对具有刚性和柔性翅膀的模型昆虫在类似的湍流环境中被拴住和自由飞行进行了数值模拟。这使得我们至少可以部分回答我们考虑的三个主要问题：(I)环境湍流对昆虫拍打飞行的空气动力学有什么影响、好处和限制？(2)湍流如何影响具有柔性和刚性机翼的扑动飞行的能量成本？(Iii)昆虫采用什么行为策略来应对动荡的扰动？这些问题既与基础研究有关，也与应用研究有关，它们的跨学科性质需要采用几个视角。