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7X24 MAGAZINE FALL 2014
Advantages in Airflow
Management by Using
Modular Containment
Managing the airflow in the computer room is key to
increased utilization, decreased energy usage and
improving the environment for IT equipment. The
components in a modular containment system allow
the data center operator to better manage airflow by
addressing the five most significant hot and cold air-
mixing areas:
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Containing cold air in cold aisles.
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Preventing airflow over the top of racks.
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Containing and directing hot air to the cooling
units.
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Filling the gaps between racks in the equipment
rows.
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Preventing conditioned or exhaust air from
flowing around the ends of equipment rows.
The Benefits of
Modular Containment
Traditionally, the separation of hot and cold air
required the implementation of fixed, highly
customized hot aisle and cold aisle containment
systems. This approach requires detailed engineering
plans, significant installation costs, disrupts the data
center operations and does not easily allow for future
rack configuration changes. Unlike hard and soft
containment designs, Modular Containment offers
complete flexibility to adapt to the current aisle
configuration without the need for engineered
services or construction within the computer room.
This means Modular Containment can be
implemented with ease and can grow and adapt with
changes in the computer room.
Specifically, Modular Containment can enable:
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A reduction in energy costs
by allowing higher
supply/return temperature set points on the
cooling units. This increases the efficiency of
cooling units by enabling a larger temperature
differential across the heat extraction coils inside
the units. In addition, this will effectively increase
the utilization of the cooling units and the total
capacity of the cooling system within the
computer room as a whole.
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Elimination of hot spots.
This can increase the
reliability of the IT equipment by providing a
lower IT inlet temperature and less thermal stress
on the components. Eliminating hot spots also
reduces energy consumption by allowing IT
equipment fans to run at a slower speed.
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Increased economizer hours
for those sites that
are taking advantage of economizers.
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Reduced humidification/dehumidification costs.
Increased cooling unit temperature set points
reduces moisture condensation on the coils (latent
cooling). This reduces — or eliminates — the cost of
latent cooling and humidification.
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Increased rack densities.
Improved airflow
management results in increased cooling capacity
to the rack, and therefore higher potential rack
densities. Modular Containment better manages
the airflow to the racks, reduces hot and cold air
mixing, and reduces bypass and recirculation air.
This allows rack densities to increase without
exceeding ASHRAE TC9.9 guidelines for rack inlet
temperatures.
The Three major benefits of airflow management
through modular containment are:
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Enabling the reduction of supply airflow volume,
which reduces operating costs and bypass airflow
volume. For data centers with fixed drive cooling
units it could mean reducing the number of
cooling units operating at any one time. For data
centers with variable speed fans it would allow the
blower speed to be reduced significantly,
reducing energy usage and costs.
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Prevention of hot air recirculation from back-to
front over the top of the racks, and around the
end of rows. This would reduce the rack inlet
temperatures at the top and along the height of
the rack and may enable increasing the set points
on the cooling units.
n
Prevention of bypass and recirculation air in gaps
between the racks in a row. Bypass air simply
goes back to the cooling unit without doing any
work in cooling the IT equipment. This is
inefficient and an energy waste. The recirculation
air coming around the side of the racks mixes with
the cold supply air and increases rack inlet
temperatures. Reducing or eliminating the mixing
may also aid in increasing the set points of the
cooling units.
