Friday, January 25th 2008
Sound Waves Can Improve Water Cooling Performance up to 147%
Sound waves can boost the efficiency of liquid cooling techniques by nearly 150%, a feat that may help keep hardworking computer chips and other components from overheating in future. Current computer cooling solutions, such as fans and heat sinks, will have difficulty keeping more powerful microchips cool in future. But researchers in the US have shown how a relatively inefficient method - liquid cooling - can be improved dramatically with the use of sound waves.
One of the best ways to remove heat quickly in high-power applications is to allow a liquid coolant to boil, so that the resulting vapour whisks away excess energy. However, this process creates tiny bubbles of vapour that can form a film over a hot surface and serve as an insulator, spoiling the cooling process.
In 2003 Ari Glezer and his colleagues at the Georgia Institute of Technology demonstrated one possible way to prevent this film from forming. They used jets of water to detach the bubbles, an approach that involved complex and bulky circulation systems.
Bubble trouble
Now Glezer's team has hit on a more efficient way to dislodge bubbles before they can coalesce into a film, using sound waves instead.
In experiments, the researchers placed an acoustic driver - essentially a speaker - sitting opposite from the heated surface, with cooling fluid in-between. They found that projecting just a small amount of sound energy, at frequencies near 1 kilohertz, across the fluid was enough to do dislodge the gathering bubbles. This increased the amount of heat that could be dissipated by as much as 147%.
The best results were achieved when the distance between the acoustic driver and the heated surface was just a few millimetres, which is good news for applications in which space is a premium. "The underwater jets solution is effective, but this way is more compact, requires less power, and is, well, more elegant," Glezer says.
Space applicationsGlezer predicts that sound-enhanced liquid cooling could find use in areas outside computing, perhaps keeping hybrid vehicles' high-powered components cool, for example.
Satish Kandlikar an expert on cooling technology at the Rochester Institute of Technology in New York, US, agrees. "This is a very interesting development," "It holds promise for applications such as chip cooling and micro-scale heat exchangers."
Kandlikar says the approach could also be suitable for keeping components cool in aircraft and space vehicles.
Source:
New Scientist Tech
One of the best ways to remove heat quickly in high-power applications is to allow a liquid coolant to boil, so that the resulting vapour whisks away excess energy. However, this process creates tiny bubbles of vapour that can form a film over a hot surface and serve as an insulator, spoiling the cooling process.
In 2003 Ari Glezer and his colleagues at the Georgia Institute of Technology demonstrated one possible way to prevent this film from forming. They used jets of water to detach the bubbles, an approach that involved complex and bulky circulation systems.
Bubble trouble
Now Glezer's team has hit on a more efficient way to dislodge bubbles before they can coalesce into a film, using sound waves instead.
In experiments, the researchers placed an acoustic driver - essentially a speaker - sitting opposite from the heated surface, with cooling fluid in-between. They found that projecting just a small amount of sound energy, at frequencies near 1 kilohertz, across the fluid was enough to do dislodge the gathering bubbles. This increased the amount of heat that could be dissipated by as much as 147%.
The best results were achieved when the distance between the acoustic driver and the heated surface was just a few millimetres, which is good news for applications in which space is a premium. "The underwater jets solution is effective, but this way is more compact, requires less power, and is, well, more elegant," Glezer says.
Space applicationsGlezer predicts that sound-enhanced liquid cooling could find use in areas outside computing, perhaps keeping hybrid vehicles' high-powered components cool, for example.
Satish Kandlikar an expert on cooling technology at the Rochester Institute of Technology in New York, US, agrees. "This is a very interesting development," "It holds promise for applications such as chip cooling and micro-scale heat exchangers."
Kandlikar says the approach could also be suitable for keeping components cool in aircraft and space vehicles.
36 Comments on Sound Waves Can Improve Water Cooling Performance up to 147%
j/k :D
just another way for them to try and milk more money out of the consumer :shadedshu
:toast:
While I am sure there are useful industrial applications, it isnt going to help consumer CPU cooling.
Of course, I am not a physicist, so I could be mistaken.
Imagine a liquid cooling system that has a liquid with a boiling point of say 50C. That liquid would absorb heat energy, convert into vapor which would later condense back into liquid, all while transferring heat at a potentially high effiency rate.
It's a very interesting concept. Essentially you would have a mini-boiler and a mini-condenser.
Fascinating research!
of course dont get near it with a match
Might be difficult geting the vapor back down to -250C to condense back to liquid.
You are absolutely right. If we put a coolant in our loops that boiled at 50C and were able to use acoustics to eliminate the vapor insulation it could definitely give an edge to OC'ers.
I am not sure it would catch on in mainstream systems, but it would definitely be cool to play with. You could pump different music through your accoustic de-vaporiser and see if Rap was better than country music to cool your rig :D
Where's the patent button? I see
I don't think heatpipes suffer from the same issue as they use a wick to move the liquid.
Lowering the pressure in the loop, so the liquid/water boils easier.
boiling points of common fluids:
Hydrogen Hydroxide - 100C
Isopropyl Alcohol - 80C
Ethyl Alcohol - 78C
Methyl Alcohol - 64C
Chloroform - 63C
Acetone - 56C
Ether - 35C
Explosive.
I was just trying to cite some examples - hell, everything I listed except rubbing alcohol is extremelly corrosive and damaging to computer hardware