Airflow Studies. What happens
in your data centre?
A good understanding of the airflow patterns and
temperature distribution in a data centre can help
improve cooling efficiency and drive improvement
efforts, especially containment system designs.
Airflow understanding is best achieved through
computer modelling of the fluid flow and thermal
processes, called Computational Fluid Dynamics (CFD)
modelling. CFD modelling can be included in an audit
or provided as a stand alone service.
Model showing before containment system
Model showing after containment system
with doors open
Air Conditioning, Containment & Control Systems (A Triple C Systems)
The A Triple C System
is a data centre efficiency practice which utilises
physical barriers to stop hot air from penetrating into
the cold aisle and adds a new controller for the CRAC
(Computer Room Air Conditioning) units. The reduction in
hot and cold air mixing increases the return air
temperature to the CRAC units. This raises the delta-T
across the CRAC units, resulting in more efficient
cooling. The isolation also creates a positive pressure
within the containment field and eliminates hot spots,
making the supply air temperature more uniform across
the server inlets. This improves efficiency while
allowing the supply air set points to be safely
increased.
When the volume of air is altered within an IT room (Data Centre), and it is cooled by an existing CRAC unit, it must be given new operating parameters. EPS has developed a new smart controller. The EPS smart controller is a unique retrofit technology designed specifically for air conditioning (CRAC units) equipment. The technology interfaces with existing controls, and is compatible with all types (large or small) of air conditioning (Vendor neutral).
The smart controller allows the cooling system to be set up, then manages a rotating master & slave system allowing the existing CRAC units to become intuitive. When more IT equipment is added to the room/racks the system will activate additional compressors as needed to stabilize the return air temperature at a predetermined temperature. Conversly, when IT equipment is removed from the room/racks the return air temperature will fall & the smart controller will reduce the number of CRAC units to meet the new demand.
The master CRAC unit will rotate to ensure an equal run-time over the life of the equipment.
The trigger points that activate the humidifier & dehumidifier within the CRAC units will be adjusted, ensuring relative humidity is controlled to meet the IT equipment specifications.
Installations to-date have shown between a 34% & 59% reduction in kWh consumption along with a ROI of under 4 years.
Economic Benefits
The A Triple C cooling solutions help separate hot and cold air, providing significant energy efficiency gains. With a complete containment solution, the following savings and benefits are available:
By minimising air mixing and allowing the
temperature difference between the supply and
return air to increase, CRAC power used can be
reduced by as much as 50% without adversely
affecting the server environmental conditions.
Higher return air temperatures increase the
efficiency of CRAC units by 30% to 49%.
With over-capacity in most data centers, excess
CRAC units can simply be turned off or put on
standby.
Rising of the supply air temperature. Many data
centers supply air at 12°C, but with
containment, that could be increased
substantially.
Allows use of higher chilled water temperature,
which would reduce the chiller plant energy use.
Increases the number of operating hours when
air-side or water -side economizer could be
used.
Reliability issues are reduced due to careful
separation of hot and cold aisles, yielding
better uniformity of the supply air temperature
at the server inlets.
Capital expenditure can be deferred and operational life of the data centre extended as more server capacity is extracted from existing facilities (i.e. stay with your present building and grow your business with your existing Air Conditioning equipment).
