View as PDF - CIBSE Journal

Figure 1: ASHRAE’s Thermal Guidelines for Data Processing Environments
underfloor to the data field, supplying
air to every second aisle of the racks of
equipment, so creating a hot and cold aisle
configuration. And by compartmentalising
each aisle all the cool supply air must pass
through the IT equipment.
This maintains it at an appropriate
temperature by removing the heat
produced by the electronic components.
The air is then extracted at high level in
the hot aisle. The air from the hot and cold
aisles does not mix and, by constraining
the flow of air to pass intimately across the
data components at a reasonable velocity,
the cooling potential of the incoming air is
maximised.
Since the range of acceptable supply
Recommended Guidelines Allowable Guidelines
Dry Bulb Temperature 18C to 27C 15C to 32C
Humidity < 60% 20% to 80%
Lower and Upper Dew
Point Temperatures
British manufacturer
T: +44 (0) 113 238 7735
E : f.farrelly@airedale.com
W: www.airedale.com/ITcooling
5.5C and 15C 5.5C and 17C
conditions is primarily determined by
the cooling effected by the air dry-bulb
temperature, evaporative humidifiers
within the air handling unit may be used
to provide adiabatic cooling. So long as the
outdoor air wet-bulb temperature is a few
degrees below the required supply dry-bulb
temperature, adiabatic cooling can reduce
the dry-bulb temperature to an acceptable
value.
This will consume water but there may
be opportunities to use desiccant systems
to exchange moisture between incoming
and discharge air to reduce
water use.
And for those days when the outdoor
air temperature is too cold to supply to the
Data centres SuStAinAbility
cIBse repuBlIc
of IrelanD
CIBSE Republic of Ireland
supports building services
engineers and helps promote the
sector in the region by accrediting
courses of study, approving
work-based training programmes
and providing routes to full
professional registration and
membership.
With more than 800
members, the region hosts
regular conferences, technical
seminars and social events.
The most recent event, which
attracted around 150 delegates,
was a one-day conference
enitled ‘Sustainable Engineering
for the Smart Economy’, at
which Marcus O’Brien gave a
presentation that formed the
basis of his article on page 42.
The region is also holding
the Irish Lighter and Young
Lighter Awards 2011. The awards,
sponsored by Enlighten and
supported by CIBSE, Dublin
Institute of Technology, Institute
of Lighting Engineers and the
Society of Light and Lighting,
are open to all building services
professionals and are now
inviting entries. A preliminary
200 to 300-word extract needs
to be submitted by 14 June – and
should cover projects in Ireland,
or lighting research.
For further information visit
www.cibseireland.org or email
kevin.kelly@dit.ie
Efficient, flexible & resilient cooling
As the leading UK manufacturer of IT cooling systems, we deliver cooling that works smarter not
harder to maximise uptime in critical, high density environments
NEW
DeltaChill
FreeCool
NEW NEW NEW
SmartCool OnRak InRak
ECHO BluCube
INTEGRATED CONTROL SOLUTIONS
CIBSE April 11 ad 65mm x 190mm.indd 1 11/03/2011 07:59
www.cibsejournal.com April 2011 CIBSE Journal 45