An introduction to Kawachi Laboratory in Department of Aeronautics and Astronautics
School of Engineering, University of Tokyo
Japanese version is HERE
An introduction to Kawachi Laboratory in Department
of Aeronautics and Astronautics
School of Engineering, University of Tokyo
Japanese version is HERE
University
of Tokyo Homepage
RCAST
Home Page
Staffs
- Dr. Keiji KAWACHI(Professor)
- Eiko SHIMIZU (Secretary)
Bio-kinetics of Flying and Swimming
The mathematical foundation of fluid dynamics was stimulated by the desire to design ships, land vehicles and airplanes - human-size objects - so that they could pass through their respective fluids with the greatest possible speed and efficiency. In contrast, until now the movement of organisms has generally been studied only by life scientists who often little understood fluid dynamics or stability control.
Interestingly, though, the hummingbird's flight mechanism is based on the same principle as that of a helicopter or a 350-ton Boeing 747 :the phenomenon of lift, utilizing a wing with a rounded leading edge and a sharp trailing edge. Smaller insects, however, such as the dragonfly, housefly or mosquito, use both lift and drag. Because the ratio of the inertial-to-viscous forces - the Reynolds number - is much different, the fluid dynamics of objects in gaseous and liquid media abruptly change at the millimeter level. The dragonfly, for instance, uses wings that are very thin and rough, which are operated at a low Reynolds number.
Understanding how small organisms fly and move in other fluids is no longer just an interesting or academic pursuit, but has become a part of interdisciplinary basic research aimed at micro-machines and other important technologies.
Helicopter is a convenient vehicle. It can fly like an insect. It climbs vertically, hovers in the sky, and takes off and lands at a small spot. Helicopter, however, has severe vibration, annoyance noise, and control problems. Prof. Kawachi dually joins with Department of Aeronautics and Astronautics, Graduate School of Engineering, as well as the Research Center for Advanced Science and Technology. He tries to solve the above problems of helicopter. The advanced technology of VTOL (Vertical Take-off and Landing Aircraft) is also included in his research subjects.
kawachi.rcast.u-tokyo.ac.jp