Study of stingray swimming could improve underwater vehicles

Mimicking the swimming expertise of stingrays could improve the agility and fuel efficiency of unmanned underwater vehicles, U.S. engineers say. "Most fish wag their tails to swim. A stingray's swimming is much more unique, like a flag in the wind," Richard Bottom, a University of Buffalo mechanical engineering graduate student, said. Bottom is participating in research to investigate the form-function relationship of the stingray; why it looks the way it does and what it gets from moving the way it does, a university release said Wednesday. Using computational fluid dynamics, the engineers have mapped the flow of water and the vortices around live stingrays. The vortices on the waves of the stingrays' bodies cause favorable pressure fields -- low pressure on the front and high pressure on the back -- which help push the ray forward, they found. "By looking at nature, we can learn from it and come up with new designs for cars, planes and submarines," mechanical and aerospace engineering Professor Iman Borazjani said. "But we're not just mimicking nature. We want to understand the underlying physics for future use in engineering or central designs." More efficient underwater vehicles could help researchers study the mostly unexplored ocean depths, and they could also serve during cleanup or rescue efforts, the researchers said.