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厦门大学博硕士论文摘要库
II
学校编码：10384 分类号 密级
学 号：32020091152450 UDC
硕 士 学 位 论 文
关于扑翼飞行器升力机制的实验研究
Experimental Investigation on the Lift Generating
Mechanism of Ornithopter
杨 琪
指导教师姓名： 鲍 锋 教 授
专 业 名 称： 航空宇航制造工程
论文提交日期： 2 0 1 2 年 月
论文答辩时间： 2 0 1 2 年 月
学位授予日期： 2 0 1 2 年 月
答辩委员会主席：
评 阅 人：
2012 年 月
关于扑翼飞行器升力机制的实验研究
杨
琪
指
导
教
师
鲍锋
教授
厦
门
大
学
关于扑翼飞行器升力机制的实验研究
杨
琪
指
导
教
师
鲍锋 教授
厦
门
大
学
厦门大学博硕士论文摘要库
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厦门大学博硕士论文摘要库
IV
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厦门大学博硕士论文摘要库
I
摘 要
扑翼飞行器在构造上是模拟自然界鸟类或昆虫类扑翼飞行的机构，如同鸟类
或昆虫类利用拍翅同时产生升力与推力。综合国内外目前的研究成果可知，低雷
诺数条件下扑翼升力机理研究具有很重要的意义。所以，本文将对低雷诺数条件
下扑翼飞行机理及其脱落涡进行探究，以对未来仿生扑翼的设计方面作出一些贡
献。
本文根据平面连杆机构原理，结合实验条件设计制作了扑翼驱动机构，为仿
生扑翼器升力机制的基础性研究做好前期准备工作。本文实验主要包括定性的色
流实验及 PIV 定量测量实验部分。
色流实验主要定性研究来流与攻角对扑翼脱体涡发展的影响。实验发现，翼
翅只有在来流与攻角缺一不可的情况下才可以产生升力。这是因为在下扑的过程
中，绝对瞬时速度比实际的瞬时速度要大，而在上扑的绝对瞬时速度在下扑过程
比实际的瞬时速度要小，导致了上翼面与上翼面所形成的脱落涡能量不一样，单
侧翼翅周围封闭流场环量守恒，所以多出来的能量便产生了升力。
在固定切面下，通过利用粒子成像测速 PIV 技术研究扑翼脱落涡的速度场
与旋度场的发展演化情况。研究结果表明，挥拍速度和扑翼攻角对脱体涡能量均
有影响，且扑翼攻角对升力改变的影响较大些。实验还对脱落涡涡心能量与脱落
涡环量的数据统计值做了拟合曲线分析，发现下扑与上扑过程所形成的脱落涡涡
心能量随时间发展的变化趋势一样，并且在挥拍极点位置处达到最大值；还发现
下扑与上扑过程所形成的脱落涡环量随时间发展的变化趋势不一样。上扑脱落涡
环量不一定小于下扑的环量，但上扑和下扑过程中脱落涡能量的最大值基本需要
经历3
5T相同的时间。PIV 实验还包括以扑动速度与攻角为变量，通过脱落涡环量
的数据统计，观察脱落涡环量随扑动速度与攻角的变化趋势与规律。
关键词：扑翼机 脱落涡 升力机制 PIV 水洞实验测量
厦门大学博硕士论文摘要库
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Abstract
Ornithopters (flapping-wing flying machine) imitate birds or flying-insects,
which can generate lift and propulsion by flapping wings. Achievements of previous
researches show that the lift generation is quite significant at low Reynolds number.
Therefore, the present paper makes relevant studies on the lift generation potentials
with respect to the vortex shedding mechanism. The present work would reveal some
essential mechanism of flapping wing lift at low Reynolds number, so as to transfer
the bionics design on flapping-wing ornithopters
According to planar linkage mechanism combined with research conditions,
flapping-wing driving device is designed and fabricated in order to make preparative
work forbasic researches on mechanism of lift force. Researches include two parts,
the qualitative part of flow visualization and the quantitative measurements using a
particle image velocimetry (abbr. PIV) system.
Qualitative researches are made to study the influence of free flow velocity and
angle of attack on shedding vortex evolution of flapping-wing device. Results show
that flapping-wing device would generate lift under conditions of free flow velocity
and with incidences of the flap wing. The reason for generating lift is that the
absolutely instantaneous velocity is bigger than the real instantaneous velocity during
flapping-wing moving downward, while, it turns out just the opposite during
flapping-wing moving upward. As a result, lift force is generated by the means of
redundant energy.
Investigation of velocity field and curl field’s evolution of separation vortex is
discussed by means of PIV measurement analysis. Results demonstrate that the lift
generation is influenced by both flapping frequency and attack angle of flapping
wings. The attack angles of flaping wings exhibit more influence on the vortex
generations, which contribute much to the lift generation. Data statistics of separation
vortex’s core energy is analyzed, showing that the variation of separation vortex’s
core energy trends similarly between upward flapping and downward flapping, and
maximum value of energy appears at poles. Data statistics also shows circular rector
of separation vortex’ trends are different. Circular rector is not always bigger than
during flapping-wing move downward, but the maximum value of energy appears the
time 3
10T later separately. Flapping velocity and angle of attack are taken as variables,
the variation trend and regular of circularrector is discussed and stated.
Keywords: Flapping wings ornithopter; Shedding vortex; Lift generating mechanism;
PIV measurement; Water-towing tank facility
厦门大学博硕士论文摘要库
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符号说明
∅(t) : 翼翅随时间变化而变化的拍动角度[°]
∅0 : 翼翅挥拍对称面/轴与轴长所成角度[°]
∅1 : 挥拍幅度[°]
ϖ : 挥拍速度，翼翅拍动频率 f 成正比[Rpm]
T : 翼翅拍动周期[s]
α t : 翼翅随时间变化而变化的俯仰角[°]
α0或 α : 攻角[°]
α1 : 俯仰对称面/轴与水平中轴所成角度[°]
φ : 拍动角度与俯仰角周期变化的相位差[°]
θmix : 翼翅与轴长所成角度的最小值[°]
θmax : 翼翅与轴长所成角度的最大值[°]
r : 偏心轴距偏心轮圆心的距离[mm]
l : 轴长长度[mm]
S : 翼翅面积[m2]
L : 翼翅展长[m]
bav : 翼翅平均弦长[m]
λ : 翼翅展弦比，无量纲数
v 或 v 来 : 自由来流速度[mm/s]
v 来 x : 自由来流速度在后缘切向分量[mm/s]
v 来 y : 自由来流速度在后缘法向分量[mm/s]
v 瞬 : 扑翼后缘所产生的瞬时速度[mm/s]
v 来绝 : 扑翼相对静止时后缘流体法向绝对速度[mm/s]
v 绝瞬 : 扑翼相对静止时后缘流体切向绝对速度[mm/s]
Re: 雷诺数，无量纲数
厦门大学博硕士论文摘要库
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目 录
符号说明 ................................................................................................. III
第一章 绪论 ............................................................................................ 1
1.1 扑翼飞行器研究背景与现状 ............................................................................ 1
1.2 扑翼飞行机理 .................................................................................................... 3
1.3 扑翼飞行器关键技术问题 ................................................................................ 7
1.4 论文主要内容与组织结构 ................................................................................ 8
第二章 扑翼实验模型设计 .................................................................... 11
2.1 扑翼驱动设计要求 .......................................................................................... 11
2.2 扑翼运动规律描述 .......................................................................................... 12
2.3 简化实验模型设计 .......................................................................................... 12
2.3.1 SolidWorks 装配体设计 ............................................................................. 12
2.3.2 模型参数实现规律.................................................................................... 14
2.4 实验模型系统 .................................................................................................. 19
2.5 本章小结 .......................................................................................................... 22
第三章 实验设备 .................................................................................... 23
3.1 精密循环水槽 ................................................................................................... 23
3.2 六分量测力天平 ............................................................................................... 24
3.3 PIV 原理及实验方法........................................................................................ 25
3.3.1 PIV 基本原理概述 ..................................................................................... 25
3.3.2 PIV 互相关算法 ......................................................................................... 26
3.3.3 PIV 系统 ..................................................................................................... 29
3.3.4 PIV 测量误差 ............................................................................................. 33
3.4 本章小结 ........................................................................................................... 33
第四章 扑翼脱体涡结构观察实验 ........................................................ 35
4.1 产生升力分析 .................................................................................................. 35
厦门大学博硕士论文摘要库
V
4.2 𝛂=0°色流定性实验 ........................................................................................... 38
4.2.1 v=0mm/s 脱落涡结构定性实验 ................................................................ 39
4.2.2 v≠0mm/s 脱落涡结构定性实验 ................................................................ 44
4.3 𝛂≠0°脱落涡切面定性实验 ............................................................................... 46
4.3.1 脱落涡端面定性实验................................................................................ 47
4.3.2 脱落涡正面定性实验................................................................................ 50
4.4 本章小结 .......................................................................................................... 53
第五章 PIV 定量实验分析 .................................................................... 55
5.1 流场速度标定 .................................................................................................. 55
5.2 速度场分析 ...................................................................................................... 56
5.3 旋度场分析 ...................................................................................................... 61
5.4 本章小结 .......................................................................................................... 66
第六章 数据统计与分析 ........................................................................ 67
6.1 环量计算 .......................................................................................................... 67
6.2 脱落涡能量发展及分析 .................................................................................. 69
6.3 扑动速度的影响 .............................................................................................. 77
6.4 攻角的影响 ...................................................................................................... 82
6.5 本章小结 .......................................................................................................... 85
第七章 总结与展望 ................................................................................ 87
7.1 总结 .................................................................................................................. 87
7.2 展望 .................................................................................................................. 88
参 考 文 献 ............................................................................................ 91
攻读硕士学位期间发表论文 .................................................................. 95
致 谢 ......................................................................................................... 96
厦门大学博硕士论文摘要库
VI
Catalogue
Nomenclature ························································································ III
Chapter 1 Introduction ············································································1
1.1 Research Background of Flapping-wing Ornithopter··································· 1
1.2 Flight Mechanism of Flapping-wing ································································ 3
1.3 Critical Technical Issues on Flapping-wing ···················································· 7
1.4 Work Contents and Organization ····································································· 8
Chapter 2 Experimental Design Model on Flapping-wing ················ 11
2.1 Design Requirements of Flapping-wing ·························································· 11
2.2 Descriptions on Flapping-wing’s Motion ······················································· 12
2.3 Design on Experimental Model ······································································· 12
2.3.1 Assembly Design by SolidWorks ····························································· 12
2.3.2 Parameter Laws of Experimental Model ·················································· 14
2.4 Experimental Model System ············································································ 19
2.5 Chapter Summary ····························································································· 22
Chapter 3 Experiment Facility ···························································· 23
3.1 Multifunctional Circulating Water Channel Facility ·································· 23
3.2 Six-components Balance System ····································································· 24
3.3 Principle of PIV and Experimental Method ················································· 25
3.3.1 PIV Fundamental Principle ······································································ 25
3.3.2 Cross-correlation Algorithm ····································································· 26
3.3.3 PIV System ······························································································· 29
3.3.4 PIV Measurement Error ··········································································· 33
3.4 Chapter Summary ····························································································· 33
Chapter 4 Experimental Observation on Shedding Vortex ·············· 35
4.1 Analysis on Lift ·································································································· 35
4.2 Qualitative Experiments on Vortex Shedding under α=0° ························· 38
4.2.1 Qualitative Experiment under v=0mm/s ·················································· 39
4.2.2 Qualitative Experiment under v≠0mm/s ················································· 44
4.3 Qualitative Experiments on Cross-sections under α≠0° ························· 46
厦门大学博硕士论文摘要库
VII
4.3.1 Qualitative Experiment on End Face ························································ 47
4.3.2 Qualitative Experiment on Main Face ······················································ 50
4.4 Chapter Summary ····························································································· 53
Chapter 5 Quantitative Measurement by PIV ··································· 55
5.1 Flow Field Calibration ······················································································ 55
5.2 Analysis on Velocity Field ················································································· 56
5.3 Analysis on Curl Field ······················································································ 61
5.4 Chapter Summary ····························································································· 66
Chapter 6 Data Statistics and Analysis ··············································· 67
6.1 Calculation on Velocity Circulation································································ 67
6.2 Development and Analysis on Separation Vortex’s Energy ······················· 69
6.3 Influence of Flapping Speed ············································································ 77
6.4 Influence of Attack Angle ················································································· 82
6.5 Chapter Summary ····························································································· 85
Chapter 7 General Summary and Outlook ········································ 87
7.1 General Summary ····························································································· 87
7.2 Outlook················································································································ 88
Reference································································································ 91
Delivered Papers during Master Degree ············································ 95
Acknowledge ·························································································· 97
厦门大学博硕士论文摘要库
厦门大学博硕士论文摘要库
第一章 绪论
1
第一章 绪论
1.1 扑翼飞行器研究背景与现状
扑翼(Flapping wing)飞行是一种模仿鸟类或昆虫飞行的新型飞行原理，基于
这种仿生学原理设计制造的飞行机器人被称为“机械鸟”或“人工昆虫”，是一
种 20 世纪末发展起来的新概念飞行器。
模仿鸟类飞行的活动在自古就有。最早的扑翼机为意大利的达•芬奇研究了
鸟翅，并利用物理和解剖知识而设想出来的用机械装置扑动人造翅膀结构的扑翼
机，本质上是模仿鸟类的人力飞行，如图 1.1 所示。1871 到 1983 年期间，Jobert’s、
Alpohnse Penaud、Lippisch 等人先后以橡筋为动力的扑翼飞行器模型，并以 Frank
Kieser1985 年实现橡筋为动力的扑翼飞行器模型最长飞行时间。通过不断的尝试
与发展，人们认识到研究者发现，只有在更好得认识及了解扑翼飞行机理的基础
上才能够设计出更好的扑翼飞行器。
图 1.1 达•芬奇设计的模仿鸟类飞行的扑翼机
Fig.1.1 Bird-imitating ornithopter designed by Leonardo da Vinci
1973 年 Weis-Fogh[1]等人以黄蜂飞行运动为研究内容进行了升力机制的探究，
并认为 clap and fling 机制(或 Weis-Fogh 机制)为黄蜂等昆虫类产生升力的原因。
1993 年 Delaurier[2][3]计算了扑翼具有挥拍及俯仰运动下的平均升力、推力和输入
功率。1994 年 Smith 计算了飞蛾翅膀在气动力和惯性力作用下翼翅的各阶弯曲
和扭转振型，并发现了柔性翼与刚性翼的区别[4]。1995 年 vest[5]等人研究了鸽子
翼翅的扭转与变形的非定常空气动力学问题。1996 年 smith[6-8]计算昆虫柔性翼翅
厦门大学博硕士论文摘要库
关于扑翼飞行器升力机制的实验研究
2
的气动力；同年，Ellington 等人发现了扇板所产生的前缘涡可以产生很大的升力
[9]。1997 年 Jones 等人通过比较单扑翼和前后组合扑翼，研究了各自非定常流场、
推力和功率的差别[10]。Tuncer[11-13]等研究了扑翼的动态失速(颤振)。1999 年 Wei
Shyy[14]等研究了柔性翼在低雷诺数情况下的空气动力学问题。
(a)Microbat (b)Entomopters
(c)SmartBird (d)翠鸟 03
图 1.2 扑翼的设计与制造
Fig.1.2 Design and manufacture of ornithopter
国内不少高等院校和科研机构虽然起步相对较晚，但也开始并加大力度开展
这方面的研究工作，以缩小与国外的差距。清华大学的曾理江等对不同昆虫飞行
机理进行了深入的研究，并发现了 Ellington 同样的研究结果[15]。北京航空航天
大学的孙茂等采用 N-S 方程模拟的方法对昆虫飞行机理进行研究，验证前缘涡产
生平动升力的机理，不过对于 Dickinson 的两个升力峰的阐释是——转动升力在
开始阶段的升力峰是由翅膀快速加速产生，结束阶段的升力峰是由翅膀快速上仰
产生[16][17]。南京航空航天大学的曾锐、昂海松等对鸟类拍翼飞行机理也进行了深
厦门大学博硕士论文摘要库
第一章 绪论
3
入研究，设计了变速-折叠翼模型，通过计算平均升力系数，认为较刚性翼，变
速-折叠翼模型升力系数有明显增加[18]。西北工业大学在实验验证方面做了大量
工作，并在昆虫和鸟类飞行机理研究基础上着手研制微型扑翼飞行器。东南大学
王姝歆等建立了柔性翅模型并进行了分析和实验研究[19]，验证了柔性翅在提高气
动效率和飞行稳定性方面的作用。此外，北京大学、安徽工业大学和厦门大学也
对昆虫飞行产生高升力的非定常机理进行了有关探讨[20]。
在扑翼飞行机理及非定常气动性研究的基础及指导下，国内外对扑翼的设计
与制造也越来越多起来。具有代表性的如日本东京大学的“人工昆虫”、美国加
州大学的“微机械飞行昆虫(MFI)”、美国加利福尼亚理工学院的“微蝙蝠
Microbat”(如图 1.2(a))、加拿大多伦多大学的微型扑翼飞行器“Mentor”、英国
剑桥大学的火星探测飞行器“Entomopter”(如图 1.2(b))，而最近德国科技公司
所研制的“Smartbird”有了突破性的进展如图 1.2(c)所示。我国的扑翼飞行扑翼
飞行相关的研究起步较晚，我国首架可控制飞行扑翼机为南京航空航天大学研制
[21],图 1.2(b)为南航的翠鸟 03，西北工业大学目前也研制了微柔性翼飞行器。
1.2 扑翼飞行机理
旋转力/Kramer 效应
我们都知道，鸟类或者昆虫在飞行过程中，翼翅并非是不扭转的，所以便产
生了旋转力(Kramer 效应)。当翼翅旋转时，总有一面的速度相对于没有旋转时
大，而另一面反之，由伯努利方程可知，当速度大时压力小，而速度小时，压力
大，如果翅膀翻转先于在上拍结束时反向旋转，那么前缘向后旋转与平移相关产
生一个向上的升力分量(反转)。如果翅膀翻转发生在拍动反向之后，旋转力将会
额外产生一个向下的力。翅膀进行旋转时，后驻点离开后缘，流动情况偏离 Kutta
条件。在重建 Kutta 条件的过程中，翅膀周围的空气流的粘性使得机翼周围产生
了额外环流，增加了升力。Kutta 条件的重建不是瞬时的，所以如果翅膀持续转
动那就很难完全实现，但是试图重建 Kutta 条件的趋势仍然会产生更大的环流。
图 1.3 中给出了翅膀如何旋转才能产生升力，在(a)中，由于 Kutta 条件，翅膀产
生了升力，当翅膀旋转时(b)，翅膀上方的空气被加速来重建 Kutta 条件。图 1.3
给出了旋转力机制的图解[21]。
厦门大学博硕士论文摘要库
关于扑翼飞行器升力机制的实验研究
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(a)
(b)
图 1.3 Kramer 效应
Fig.1.3 Kramer Effect
前缘涡/延时失速
图 1.4 二维和三维运动的延时失速机制
Fig.1.4 2D and 3D of Delayed Stall Mechanism
厦门大学博硕士论文摘要库
Degree papers are in the “Xiamen University Electronic Theses and Dissertations Database”. Fulltexts are available in the following ways: 1. If your library is a CALIS member libraries, please log on http://etd.calis.edu.cn/ and submitrequests online, or consult the interlibrary loan department in your library. 2. For users of non-CALIS member libraries, please mail to [email protected] for delivery details.
厦门大学博硕士论文摘要库
