Bubble mattress reduces drag in fluidic chip

May 14, 2013

Researchers at the University of Twente's MESA+ research institute have given the first demonstration of how the drag exerted on liquids flowing through tiny "fluidic chips" is affected by the introduction of diminutive gas bubbles. Armed with this knowledge, scientists can directly manipulate flow resistance in a variety of applications involving combinations of liquids and gas bubbles. This could be useful in areas ranging from the manufacture of fizzy drinks to the development of artificial lungs.

This research has been published in the Proceedings of the National Academy of Sciences (PNAS).

The theoretical principles of how the shape and size of gas bubbles affect the drag exerted on an overlying fluid were already well understood. Even though this area has been the subject of intensive research for more than twenty years, the precise details of this relationship have only recently been experimentally demonstrated. Researchers at the University of Twente's MESA+ research institute have now developed a tiny "fluidic chip" that can be used to accurately measure the extent to which miniscule affect the drag exerted on flowing .

Using this approach, the researchers in this study measured a 21 per cent reduction in the of liquids passing across the chip. Prof. Rob Lammertink, one of the scientist involved, says that even greater reductions are definitely achievable.

Fluidic chip

The fluidic chip developed in this study features two minute channels, running parallel to one another, each with a diameter of only 100 micrometres (one micrometre is a thousand times smaller than a millimetre). A liquid flows through one of these channels and a gas through the other. These minute channels are interconnected by even smaller channels, which are used to introduce diminutive bubbles of gas (about ten micrometres in diameter) into the liquid. These tiny bubbles coat the wall of the fluid channel, forming a "bubble mattress". This affects the drag exerted on any liquid flowing across that area. By varying the gas pressure, the researchers can control the size and shape of the bubbles. This allows them to accurately measure the bubbles' effect on the drag exerted on the liquid.

While the research in question involves extremely fundamental physics, Prof. Lammertink is convinced that it will eventually generate a range of practical applications. "Such knowledge could be useful in the development of artificial lungs, for example, in which blood is oxygenated by flowing across an artificial membrane. Another potential application is dissolving carbon dioxide in fizzy drinks, such as cola."

The article is titled "Control of slippage with tunable bubble mattresses."

Explore further: New complex oxides could advance memory devices

More information: www.pnas.org/content/early/2013/05/01/1304403110

Related Stories

Mysterious nanobubble burst?

Dec 02, 2008

(PhysOrg.com) -- The nanobubbles that develop on submerged surfaces should not really be able to exist. Because of the enormous internal pressure, they should disappear within a short time. Nevertheless, they ...

Explosion on chip sets liquid in motion

Oct 30, 2008

(PhysOrg.com) -- PhD student, Dennis van den Broek, of the University of Twente, Netherlands, has developed a new type of miniature motor, the micro-bubble actuator. This ‘motor’, which can be used in ...

Recommended for you

New complex oxides could advance memory devices

4 hours ago

The quest for the ultimate memory device for computing may have just taken an encouraging step forward. Researchers at The City College of New York led by chemist Stephen O'Brien have discovered new complex ...

And so they beat on, flagella against the cantilever

Sep 16, 2014

A team of researchers at Boston University and Stanford University School of Medicine has developed a new model to study the motion patterns of bacteria in real time and to determine how these motions relate ...

Tandem microwave destroys hazmat, disinfects

Sep 16, 2014

Dangerous materials can be destroyed, bacteria spores can be disinfected, and information can be collected that reveals the country of origin of radiological isotopes - all of this due to a commercial microwave ...

Physicists design zero-friction quantum engine

Sep 16, 2014

(Phys.org) —In real physical processes, some energy is always lost any time work is produced. The lost energy almost always occurs due to friction, especially in processes that involve mechanical motion. ...

User comments : 0