Physicists have created a machine which can draw in floating objects by using waves. The waves create currents in the water and could be used to contain oil spills.
Physicists at the Australian National Laboratory (ANL) have created a machine that, by producing waves, can act as a tractor beam on water. The scientists, led by Professor Michael Shats and Dr. Horst Putzmann, discovered that certain wave patterns move liquids in different directions, and by using a simple wave generator, they could draw in objects at will. “We have figured out a way of creating waves that can force a floating object to move against the direction of the wave,” said Dr Punzmann, from the Research School of Physics and Engineering.
At first, this might simply seem like nothing all that spectacular, but once you consider the practical applications, the new discovery becomes very exciting. Oil spills, for example, could be contained using a wave generator like the one used by the research team. The physicists tested the machine by generating waves in a water tank which moved a ping pong ball in any direction they chose. The team also tried different shaped plungers (used to create the waves) to see if they could create different flow patterns in the water.
Dr. Punzmann and Prof. Shats, testing the tractor beam
A particle tracking tool, developed by Dr Nicolas Francois and Dr Hua Xia shows that under certain frequencies, waves generate a current on their surface. “We found that above a certain height, these complex three-dimensional waves generate flow patterns on the surface of the water,” Professor Shats said. “The tractor beam is just one of the patterns, they can be inward flows, outward flows or vortices.”
At this time, there is no mathematical theory that can explain the currents generated by the waves. “It’s one of the great unresolved problems, yet anyone in the bathtub can reproduce it.” says Dr. Punzmann, “We were very surprised no one had described it before.”
Source: Science Daily