Download Energy efficiency and liquid cooling

Energy efficiency and liquid cooling
computing system
20°C
DRY COOLER
25°C
rack 1
30°C
rack 2
rack #n
50°C
30°C
ENERGY RECOVERY
50°C
The scientific and industrial world is facing a dramatic growth in their computational needs, driving
up the power consumed by CPU and GPU based systems. The increased density of HPC clusters
and supercomputers creates the necessity to extract huge quantities of heat generated in very little
space. Traditional cooling via air conditioning not only is becoming a consistent economic burden,
but often is simply not enough to cool high density systems.
Aurora liquid cooling
BENEFITS
• Lower operational costs
• More density
• Power savings and power availability
• Reduced hot spots (datacenter and on-board)
• Reduced carbon foot print
• No fans, no vibrations, no noise
FEATURES
• Dry cooling with no chillers
• Avoid air conditioning
• Direct on component liquid cooling
• Water up to 50 °C
• Pressure, 2 to 4 bars
• Quick disconnects for hot swaps
ELECTRICAL POWER IN
CHILLER 23%
HUMIDIFIER 3%
IT EQUIPMENT 47%
PUE = 2.13
INDOOR
DATA CENTER
HEAT
PDU 3%
HEAT OUT
CRAC/CRAH 15%
UPS 6%
LIGHTING/AUX DEVICES 2%
SWITCHGEAR/GENERATOR 1%
Figure 1: Typical power distribution in a data center (source APC)
Energy efficiency in data centers
Liquid cooling
Only a percentage of the power coming to a datacenter is
actually utilized by the servers (the IT load), while the remaining is either utilized for ancillary services, like cooling, or
wasted.
Figure 1 adds some details on how typically power is distributed in a data center. The reported PUE of 2.13 is an
average value in a temperate climate. That means per every
W of power consumed by the datacenter, only 1 W goes
to feed usefully the IT load, while the remaining 1.13 W is
utilized between air conditioning and waste.
Eurotech Approach
Eurotech approach to the energy problem is to tackle the
efficiency of the entire data center, not only of the machine
itself.
Two levers to leap forward in energy efficiency are:
•
Power conversion efficiency
•
Cooling
In an Aurora system, computational node cards, control
cards, Infiniband switches and power conversion units are
cooled using liquid circuits.
The unique feature of Aurora, as an HPC system, consists
in the fact that the whole heat that components generate is
removed through liquid circulation.
The main components of the Aurora cooling infrastructure
are:
•
cold plates
•
liquid distribution bars
•
dry coolers (liquid to air heat exchangers)
•
liquid distribution bars inside each rack
•
pipes
•
optional chillers and pumps
Each Aurora rack has two 2” pipes (actually, four couples
per rack), one for inlet, one for outlet of cooling liquid. Inside
each rack, the liquid is distributed to the different cold plates, utilized to directly cool the components. The cold plates
are fitted to the distribution channels via quick disconnect
hydraulic connectors. Lines of connectors are mounted on
Power conversion
the chassis backplane to allow hot swapping of any of the
Power conversion in Aurora systems takes place in two separate steps. 400-200VAC is converted to 48VDC by high
(97%) efficiency ACDC converters. The chassis receives a
48VDC supply, which has an advantage in safety terms: Aurora is a low voltage equipment. 48VDC are in turn stepped
down to 12VDC, reaching all Aurora boards, by a PSU within
each chassis (DCDC Tray) with 97% efficiency.
computation nodes. The coolant is collected from the cold
plates into the outlet pipes. The inlet and outlet pipes are
connected to the liquid circuit that brings the water to the
heat exchanger. In here, the liquid is cooled and returns to
the racks.
The water in the circuit can be as hot as 50 °C, making it
possible to deploy Aurora in virtually any climate zone.
Information in this document is provided in connection with Eurotech products. Except as provided in Eurotech’s terms and conditions of sale for such products, Eurotech assumes no liability
whatsoever, and Eurotech disclaims any express or implied warranty relating to sale and/or use of Eurotech products, including liability or warranties relating to fitness for a particular purpose,
merchantability, or infringement of any patent, copyright, or other intellectual property right.
Specifications and features subject to change without notice. All trademarks and tradenames are the property of their respective owners.
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www.eurotech.com/aurora