London, January 18 : A chemical engineer at the University of New Brunswick, Canada, has come up with an idea to keep drinks flowing in space.
Brian Lowry says that "cups" made from corkscrews of ribbon-like material may one day enable space tourists to drink coffee. The researcher says that holding liquids this way may solve the tricky problem of getting fluid out of an open container in microgravity. Nanotechnologists working with tiny samples of liquid may also find this approach useful, he adds.
Gravity on Earth lets liquids to pour from an open container, but it may require pumping or sucking through a straw in microgravity.
Many times, the fluid breaks up into globules in space due to the way pressure inside the liquid interacts with the shape of most containers.
"You can withdraw it up to a point, but then end up with fluid sticking around the bottom of the glass. You have to chase around to get it all out," New Scientist magazine quoted Lowry as saying.
He says that this impact is problematic for space engineering systems, which need to transport liquids to keep spacecraft running smoothly, also.
The normal solution is to pressurise containers so that liquid is driven out whenever a vent is opened, he adds.
An alternative solution can be the use of helical shapes, says Lowry, who has analysed this idea with his colleague Heather-Jean May, another researcher from the University of New Brunswick.
The researchers say that such forms may function much better as containers for holding fluids in microgravity, for surface tension holds liquid inside the coil and the properties of the shape's surface allow fluid to be sucked out in one go.
As liquid is drawn out of the helical containers, the remaining fluid redistributes along the spiralling support. This may enable astronauts to drain a helix holding a drink in a single draught.
"They are like open tanks, so you can drain fluid or add fluid. It's an odd geometry, but they behave very much like coffee cups," says Lowry.
The idea of using a helix originally came from David Thiessen at Washington State University, who was inspired by a notebook binding.
Lowry's team used mathematical models work out the ideal helix for space containers. The researchers tested the candidates in a tank that simulated microgravity, using two different liquids of equal density.
They hope that their designs will one day be tested in true microgravity.
Lowry believes that helical containers could also make it easy to build spacecraft systems and design microgravity experiments.
"Heat exchangers are one example. These containers act much like tanks and pipes on earth do so they are more intuitive to build with," he says.
The approach may also be useful in other scientific areas, Lowry adds.
"At the micro and nano scale, gravity becomes relatively
insignificant, so this approach could help engineers working with
tiny amounts of fluid on earth too," he said.