Case Studies

Investigation of Flight in Nature
Washington, D.C. - April 2002

Contributed by: Dr. Rajat Mittal Flow Simulation and Analysis Group George Washington University

Flow simulation of an insect in hover. Understanding flying in nature may help design better micro air vehicles.

Since the dawn of time, humans have been in awe of flying. With modern technology and computing power, it is now possible to solve many of the mysteries surrounding flight.

The Flow Simulation and Analyses Group (FSAG) at George Washington University has developed a unique flow solver capable of accurately simulating flows around complex moving bodies — including flapping insect wings.

Their hovering insect animation demonstrates the dynamics of flapping wing flight. The simulation is part of their research that analyses the physical mechanisms associated with biological flight and swimming mechanisms.

Currently there is significant interest in biomimetic micro machines — like micro aircraft and micro submarines. Nature has already figured out the best mechanisms for locomotion (swimming and flying) at small scales. FSAG hopes that by understanding swimming and flying in nature they can help design better micro machines.

Micro machines may have many potential uses. For defense purposes, micro aircraft could fly military spy missions inside buildings, provide instant information about battlefield environments, or sip behind enemy lines to snap reconnaissance photographs.

Movement of wingtip and wing surface during forward flight. Courtesy W. Nachtigall

FASG analyses the physics of complex flows with numerical simulations. They run larger simulations on massively parallel computers at National High Performance Computers Centers. They also have a significant in-house computing capability in their CFD lab. This houses a cluster of high-end single and dual processor UNIX workstations and PCs.

Dr. Rajat Mittal is an assistant professor in the Mechanical and Aerospace Engineering Department and heads the Flow Simulation and Analyses Group (FSAG). "Tecplot is an integral part of our analysis...and saves us a great deal of time. It is used to visualise and analyse our results," he says.

Aerodynamics of dragonfly dual wings.
View AVI animation (2,660 KB)

Combined pitch and heave motion of a flapping insect wing.

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