Heat Output, Airflow, And Cooling; Example Of Cold Aisle/Hot Aisle Rack - IBM DS3500 Installation, User's, And Maintenance Manual

Heat output, airflow, and cooling

Air enters at the front of the DS3500 storage subsystem and EXP3500 storage enclosure and leaves at the
back. Allow at least 30 inches in front of the DS3500 storage subsystem and EXP3500 storage enclosure
and at least 24 inches at the rear for service clearance, proper ventilation, and heat dissipation.
When racks that contain many DS3500 storage subsystems and EXP3500 storage enclosures are to be
installed together, the following requirements must be met to ensure that the devices are adequately
cooled:
v Air enters at the front of the rack and leaves at the back. To prevent the air that is leaving the rack
from entering the intake of another piece of equipment, you must position the racks in alternate rows,
back-to-back and front-to-front. This arrangement is known as "cold aisle/hot aisle" and is shown in
Figure 1-15.
v Where racks are in rows, each rack must touch the rack that is next to it to reduce the amount of hot
air that can flow around from the back of the rack into the intakes of the storage enclosures that are in
that rack. Use Suite Attach Kits to completely seal any gaps that remain between the racks. For details
about Suite Attach Kits, contact your IBM marketing representative or authorized reseller.
v Where racks are in rows front-to-front or back-to-back, gaps of at least 122 cm (48 in.) must separate
the rows across the cold aisle (see Figure 1-15).
v To correct airflow in each rack, the rack filler plates must be installed in unused positions. Also, all the
gaps in the front of the racks must be sealed, including the gaps between the storage subsystems.
120 cm (48 in.)
cold aisle width
Figure 1-15. Example of cold aisle/hot aisle rack configuration
1-20
System Storage DS3500 and EXP3500: Installation, User's, and Maintenance Guide
T42 racks
Cold aisle
T42 racks
Hot aisle
T42 racks
Airflow
back
front
Perforated tiles
or gratings
front
244 cm (96 in.) between
center lines of hot
and cold aisle
back
back
front