'Nano-lightning' instead of fan to cool your laptop

April 23, 2004

Jumping electric charges could waft breezes of ionised air through microchips, replacing the bulky and noisy fans that cool down today's computers.
Researchers at Purdue University in West Lafayette, Indiana said that their patent-pending technology could be built directly into a computer chip's heat sink to provide a faster, quieter and lighter cooling system than existing alternatives.

In current designs, a metallic sink absorbs the heat generated by currents in the microchip and is cooled by mechanical fans. But as engineers squeeze more functionality out of smaller chips, they are finding that the fans cannot cool down the chips fast enough or are too big for the device.
"Heat is now a major factor limiting the size of laptops," said Dan Schlitz of Purdue University.
Therefore, researchers have come up with a range of alternatives, including piezo-electric fans and tiny, cold-water pumps. However, there is always a trade-off because air is preferable to water and it is does not need to be encased, but water is attractive because it absorbs and releases heat more quickly.
The Purdue technology is the first air-based system to produce a cooling rate similar to water - 40 watts per square centimeter as reported in the New Scientist.
"That is why we are excited," said Suresh Garimella, who led the research and is engaged in seven other chip-cooling projects.
The secret is producing the airflow right at the wall of the heat sink. The new system consists of 300 electrodes that ionise and then pump the air molecules across the surface.
On one side of the device are the negatively charged electrodes, bristling with long, slender carbon nanotubes to concentrate the electric field. When the voltage is switched on, electrons jump the 10 microns from the negative to positive electrodes.
This knocks electrons off the air molecules to produce a cloud of positively charged ions. While the phenomenon is similar to lightning, it occurs at much lower voltages and no actual sparks are produced.
The efficiency with which the voltage is converted into electrons is as yet unknown. But any leftover voltage will be converted into heat, which hampers the cooling effect.
"This kind of electrically driven flow traditionally has low rates of conversion," said Garimella.

"This is promising research, but there are a range of competing technologies," noted Richard Smith, who studies heat dissipation in electronic systems at the US National Science Foundation, which funded the research.

related links:
in.tech.yahoo.com/040325/139/2c77i.html
www.newscientist.com/hottopics/tech/article.jsp?id=99994816&sub=Nanotechnology
www.purdue.edu/

Explore further: Hong Kong swelters on hottest day in history

Related Stories

Cool paint job could blow away air con costs

July 20, 2015

A cool discovery from QUT researchers has found that a special roof coating could bring Queenslanders relief from sweltering summers as well as lower electricity bills.

Recommended for you

A marine creature's magic trick explained

September 2, 2015

Tiny ocean creatures known as sea sapphires perform a sort of magic trick as they swim: One second they appear in splendid iridescent shades of blue, purple or green, and the next they may turn invisible (at least the blue ...

Prawn Nebula: Cosmic recycling

September 2, 2015

Dominating this image is part of the nebula Gum 56, illuminated by the hot bright young stars that were born within it. For millions of years stars have been created out of the gas in this nebula, material which is later ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.