Bulletin of the American Physical Society
64th Annual Meeting of the APS Division of Fluid Dynamics
Volume 56, Number 18
Sunday–Tuesday, November 20–22, 2011; Baltimore, Maryland
Session A6: Insect Flight I |
Hide Abstracts |
Chair: Z. Jane Wang, Cornell University Room: 309 |
Sunday, November 20, 2011 8:00AM - 8:13AM |
A6.00001: Impulse perturbation and recovery in a free flying insect Tyson Hedrick, Jeremy Greeter Flying animals are renowned for their ability to recover from substantial perturbations due to environmental turbulence, contact with other objects, or other sources. These capabilities are due to the underlying aerodynamics of flapping flight (its open-loop properties) and feedback control based on the neurosensory inputs, the combination providing the animal's closed-loop response. Here we examine the sources of perturbation resistance and recovery in a flying insect by delivering a pitch impulse perturbation to hovering hawkmoths (\textit{Manduca sexta}) while characterizing the response of the animal using high-speed stereo videography. The closed-loop neurosensory and open-loop aerodynamic components of the response were then separated by comparing the observed response dynamics of the animal to those predicted from a variety of open loop models and simulations of hawkmoths. We found that the moth's perturbation response was dominated by its open-loop aerodynamic properties, which include sufficient damping to rapidly slow the pitch perturbation. A slower sensory response helped bring the moth back to a level orientation. [Preview Abstract] |
Sunday, November 20, 2011 8:13AM - 8:26AM |
A6.00002: Improved Low-Order Models of Bio-inspired Pitching and Perching Chengjie Wang, Jeff D. Eldredge To study the flying of small creatures, their simplest flapping motions, pitching and perching, are investigated by low-order inviscid point vortex models. These motions induce coherent vortex shedding at the leading edge, which has a profound influence on the generated force. Instead of fully recovering the flow field around wing, the reduced models track only small number of discrete vortices with time-varying strength to account for the unsteady aerodynamics. The idea of impulse matching is introduced to develop the new governing equation, different from the previously-developed Brown-Michael equation. For both pitching and perching motions, the results from the impulse matching model are compared with high fidelity simulations under different pitching rate and axis position, and this comparison shows a good qualitative agreement, which is better than obtained with the Brown-Michael approach. The results are also compared with previous experiments conducted in a water tunnel, and good qualitative agreement is achieved. Further, some detailed analysis of the high fidelity simulation has been performed to get intuition about the leading edge vortex, which can help us in improving the low-order model. [Preview Abstract] |
Sunday, November 20, 2011 8:26AM - 8:39AM |
A6.00003: Low Dimensional Modeling And Computational Analysis of Dragonfly Wing Aerodynamics Yan Ren, Hui Wan, Haibo Dong High-fidelity numerical simulations are being used to examine the key aerodynamic features and lift production of insect wings. However, the kinematics of the insect's wing and the resulting aerodynamics is highly complex, and does not lend itself easily to analysis based on simple notions of pitching/heaving kinematics or lift/drag based propulsive mechanisms. A more inventive approach is therefore needed to dissect the wing gait and gain insight into the remarkable aerodynamic performance of the insect's wing. The focus of the current investigation is on the aerodynamics of the wing of a dragonfly (Erythemis Simplicicollis) in hovering motion. The three-dimensional, time-dependent wing kinematics is obtained via a high-speed photogrammetry system. Singular Value Decomposition (SVD) is then applied to extract the essential features of the wing gait. The SVD spectrum shows that the first four modes capture more than 80{\%} of the motion. Aerodynamics of wings flapping with kinematics synthesized from SVD modes will be discussed in detail. [Preview Abstract] |
Sunday, November 20, 2011 8:39AM - 8:52AM |
A6.00004: Flight Forces Control Strategy in Insects Samane Zeyghami, Haibo Dong Introducing a new point of view to steering muscles activity in insects, we are proposing a new flight forces control strategy that shows strong compatibility with many experimental observations. We have proven that the flight forces alternations can be controlled without direct control of wing's kinematic parameters. According to the proposed method choosing appropriate phase shift in steering muscles' activity between bilateral wings, insect is able to do desired maneuver. In fact correlation between the wing's motion and aerodynamic forces could give the insect high level of control on the flight forces magnitude and direction while requiring much simpler control system and lower power input. [Preview Abstract] |
Sunday, November 20, 2011 8:52AM - 9:05AM |
A6.00005: Wing Damage Effects on Dragonfly's maneuverability Zhe Ning, Kuo Gai, Samane Zeyghami, Haibo Dong In this work, how the insect flight behavior contributes to its adaptability to limited performance condition is studied through a combined experimental and computational study. High speed photogrammetry is used to collect the data of dragonflies' takeoffs with intact and damaged wings along the chord and span separately. Then the effect of the spanwise and chordwise damage on the dragonfly wing is investigated. Results show that both changes have different effects on the wing and body kinematics and the merit of maneuverability. Two theories will be introduced to explain the wing damage tolerance behavior of the dragonfly flight. [Preview Abstract] |
Sunday, November 20, 2011 9:05AM - 9:18AM |
A6.00006: Observation of the wing deformation and the CFD study of cicada Hu Dai, Shahrizan Mohd Adam Das, Haoxiang Luo We studied the wing properties and kinematics of cicada when the 13-year species emerged in amazingly large numbers in middle Tennessee during May 2011. Using a high-speed camera, we recorded the wing motion of the insect and then reconstructed the three-dimensional wing kinematics using a video digitization software. Like many other insects, the deformation of the cicada wing is asymmetric between the downstroke and upstroke half cycles, and this particular deformation pattern would benefit production of the lift and propulsive forces. Both two-dimensional and three-dimensional CFD studies are carried out based on the reconstructed wing motion. The implication of the study on the role of the aerodynamic force in the wing deformation will be discussed. [Preview Abstract] |
Sunday, November 20, 2011 9:18AM - 9:31AM |
A6.00007: ABSTRACT WITHDRAWN |
Sunday, November 20, 2011 9:31AM - 9:44AM |
A6.00008: Active Deformation in Insect Wings and Its Effect on Aerodynamic Performance of Flapping Flight Lingxiao Zheng, Rajat Mittal, Tyson Hedrick While passive deformation in insect wings during flight is well know, we demonstrate the presence of significant active deformation in the wings of butterfly. High-speed videography is used to capture wing kinematics of a Painted Lady butterfly flying freely inside an enclosure. An analysis of the videos shows that the chordwise deformation in the wings of this insect is inconsistent with passive (flow or inertial induced) deformation. It therefore follows that the deformation is produced actively by the insect. Computational fluid dynamics analysis is used to examine the effect of this active deformation on aerodynamic performance and results from this study will be presented. [Preview Abstract] |
Sunday, November 20, 2011 9:44AM - 9:57AM |
A6.00009: Understanding Flight Stabilization In Insects to Large Perturbations Using an Integrated Experimental-Numerical Approach Chao Zhang, Lingxiao Zheng, Ty Hedrick, Rajat Mittal Insects adopt a variety of strategies to stabilize flight in the face of large-scale aerodynamic and mechanical perturbations. Linear stability analysis and simple estimation techniques such as blade-element models can only provide very limited insights into these strategies since the response is highly non-linear and far from simple equilibrium conditions. In order to tackle this problem, we have coupled a Navier-Stokes immersed boundary-based solver to a six degree-of-freedom (DOF) flight dynamics model of a Hawkmoth (Manduca Sexta) to model this stabilization process in all its complexity. The model is used to examine the response of this insect to large-scale aerodynamic and mechanical perturbations and results from this study will be presented. [Preview Abstract] |
Sunday, November 20, 2011 9:57AM - 10:10AM |
A6.00010: Understanding the Role of Moment-of-Inertia Variation in Insect Flight Maneuvers Tiras Lin, Rajat Mittal, Lingxiao Zheng, Tyson Hedrick The objective of this study is to gain insights into insect flight maneuvers and, in particular, the role that changes in body moment-of-inertia might play during these maneuvers. High-speed, high-resolution videogrammetry is used to quantify the trajectory and body conformation of Painted Lady butterflies during flight maneuvers; the 3D kinematics of the center-of-masses of the various body parts of the insect are determined experimentally. Measurements of the mass properties of the insect are then made and used to parameterize a simple flight dynamics model of the butterfly. Even though the mass of the flapping wings is small compared to the total mass of the insect, these experiments and subsequent analyses indicate that changes in moment-of-inertia during flight are large enough to have a noticeable impact on the maneuvers of these insects. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700