Passive cooling technique could slash computer hardware costs
27 April 2015
Processor cooling technique could save computer manufacturers $540 million annually in manufacturing material costs by eliminating fans and associated wiring.
The system, developed at the University of Alabama in Huntsville (UAH), uses convection to circulate 3M’s Fluorinert FC-72 liquid through channels in a computer’s processor and then into a heat sink that serves as an external radiator.
Fluorinert FC-72 electronic cooling liquid and electrical insulator is a colourless, odourless, biologically inert and chemically stable dielectric liquid that is non-flammable and has a boiling point at 56°C.
In the passive system’s convection cycle, heat from the computer processor vaporises liquid FC-72. The light vapour moves to a heat exchanger, releases its heat into the environment and condenses into a heavier liquid, then moves to a holding tank, from which the liquid travels to the processor once again to complete the cycle.
Under the supervision of UAH's Professor James Smith, graduate student, Cuong Nguyen compared the passive cooling system with traditional solid-state passive cooling and traditional fan cooling in computers running for up to 12 hours under no load and heavy load conditions. The system was tested using modified Intel Pentium 4 and Core i3 processors.
Nguyen's experiments found that a near steady state 56°C processor operating temperature was achieved using the system. The acceptable range of processor operating temperature is 50-90°C.
“When we remove the cooling fan, it saves material costs, but it also eliminates the noise, vibration and dust contamination of fan cooling,” Nguyen says.
Optimised liquid passive cooling has a range of potential applications beyond home and business computers. Professor Smith and his team believe the system could prove useful in temperature stabilisation of electronic guidance and propulsion controls in outer space, as well as finding application in efficient 21st century power delivery systems.