Most folks find it hard enough to cool server installations dealing with megaflops and gigaflops, and are glad they don't have to worry about petaflops of processing power. Not so for Cray Inc. (CRAY), which specializes in supercomputers. Cray said this week that it has introduced a liquid cooling technology that will allow computers to operate at "unprecedented speeds of multiple petaflops (thousands of trillions of calculations per second) while delivering significant energy savings." Cray XT5 systems will begin shipping with the company's new ECOphlex (short for PHase-change Liquid EXchange) technology later this year.
Cray's ECOphlex-equipped cabinet has the flexibility to use either vertical air cooling or a new liquid evaporative phase-change cooling technology that converts an inert coolant, R134a, from a liquid to a gas. ECOphlex systems can also use chilled or unchilled water at various temperatures, reducing the need for many CRAC units. R134a, also known as Tetrafluoroethane, is an inert gas used in refrigerators and automobile air conditioners.
"Most large computers today exhaust heat into the air, and then the Computer Room Air Conditioner [CRAC] units have to remove the heat from the air and put it into chilled water," said Cray Chief Technology Officer Steve Scott. "This method is very inefficient. For a petascale system, the area taken up by the CRAC units could exceed the computer footprint, wasting precious data center space and energy. Other systems use chilled water coils embedded in each computer cabinet and sometimes even embedded invasively into the compute blades.
"With ECOphlex technology, you still use chilled water, but much less of it," Scott added. "And because of our unique engineering, you don't need to worry about water condensation or leakage that could harm electronic components. ECOphlex technology allows HPC sites, large or small, to enter the muli-petaflops era, tackle the most daunting science and engineering problems, and apply large numbers of high-performance processors at industry-leading densities while achieving strong energy efficiencies on a broad spectrum of applications."