A team of IBM researchers in Switzerland is experimenting with a micro network of copper tubes that run through smaller, clustered computer servers and whisk away heat with the help of warm water. Liquid cooling, even with warm water, is 4,000 times more effective than air cooling at removing heat, they say. Researchers from IBM and the Swiss Federal Institute of Technology in Zurich report in the April 16 issue of Science that early testing of a supercomputer they created and dubbed Aquasar indicates it uses half the electricity of a supercomputer cooled with cold water (which requires electric chillers to keep the water at about 15 degrees C). Aquasar uses 60-degree-Celsius water instead of air as its coolant to capture and remove heat.
Read more from Scientific American.
Aquasar, a supercomputer built by IBM and ETH Zurich, will have water-cooled IBM blade servers as the one pictured. © IBM RESEARCH – ZURICH/MICHAEL LOWRY
Martin Pitasi says
My name is Marty Pitasi, Senior Thermal Mechanical Design Engineer and the principal inventor of a similar technology for board level cooling. I am writing to you because I would like to share my 8 years of knowledge and experience to accelerate the development of the technology.
In 1989 I develop a small envelop, low noise, high performance liquid cooling system for an advanced 6.4kW (16 tier/400W) Enterprise computer (rack). During the development of the proof-of-concept system design; solutions for coolant distributions at the board and cabinet levels, supply and return manifolds, a board to manifolds interfacing, and component to board heat exchanger design were solved. My background would be of value to your development program. It would reduce your time to market and improve quality and reliability.
To meet the cooling design package envelop, noise, performance, and power constraint a Pumped Liquid Refrigerant Cooling (PLRC) System is suggested. PLRC technology is a quasi-isothermal cooling design that depends on the latent-heat-of-vaporization as the cooling mode. Pumped sub-cooled refrigerant is circulated through load heat exchanger(s), thus, causing the refrigerant to change phase, final the vapor is converted back to a sub-cooled liquid via the condenser. A simple feedback control loop maintains the vapor quality between 20% and 80%.
System test results of a proof-of-concept design with 16/400W parallel sources showed COP values of 17 and 70 for air and water condensers, respectively. The advantage of refrigerant cooling over water, EGW, PGW, and de-ionized water include lower flow rates and pressure drops, elimination of potentially harmful contaminates, low dielectric strength, and a simple feedback control loop. To support the cooling effectiveness a custom heat exchanger design was developed. The results of over 100 tests cases consistently showed that the PLRC heat exchanger design delivered a vapor-to-surface conductance value of 10W/°C-CM2. Correspondingly, the flow rate, pressure drop, and coolant temperatures were 2.0 GPH at 2.0 PSID, and 40°C, respectively.
Assuming this would be of interest, design and test data are available for review.