The Department of Energy‘s Sandia National Laboratories has developed a radically new way to remove heat from computer components using a design that is 30 times more efficient than current heat exchangers.
In conventional systems, metal fins, combined with a fan, transfer heat away from sensitive part. But heat still gets trapped in the pockets of air in that adheres to and envelops all surfaces, or boundary areas, of the heat exchanger.
The build up of heat, combined with particulate matter and other airborne contaminants, or fouling, eventually reduces performance and adds to the cost of keeping computers cool.
Another problem is that the small and medium-sized fans used to keep units cool have relatively poor mechanical efficiency and tend to produce high noise levels.
The “Sandia Cooler” architecture simultaneously eliminates all three of the drawbacks of conventional air-cooled heat exchanger technology through an entirely new design that essentially merges the heat exchanger with the fan, creating a rotating heat exchanger, according to Sandia researchers.
In this new device, heat is efficiently transferred from a stationary base plate to a rotating structure that combines the functionality of cooling fins with a centrifugal impeller. Dead air enveloping the cooling fins is subjected to a powerful centrifugal pumping effect, providing a 10-time reduction in boundary layer thickness at a speed of a few thousand revolutions per minute.
The high-speed rotation completely eliminates the problem of heat exchanger fouling. The “direct drive advantage”, in which relative motion between the cooling fins and ambient air is created by rotating the heat exchanger, provides a drastic improvement in aerodynamic efficiency. This translates to an extremely quiet operation.
The result provides a several-fold reduction in boundary layer thickness, intrinsic immunity to heat sink fouling, and drastic reductions in noise. In addition, it is also expected to be very practical from the standpoint of cost, complexity, ruggedness, say Sandia officials.
The benefits have been quantified on a proof-of-concept prototype. Sandia National Laboratories is managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corp., for the U.S. Department of Energy’s National Nuclear Security Administration under contract.