IBM 9008-22L, Планирование площадки и оборудования

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Air exposure:
The secondary cooling loop is a closed loop, with no continuous exposure to room air. After you fill the
loop, remove all air from the loop. An air bleed valve is provided at the top of a heat exchanger
manifold for purging all air from the system.
Water delivery specifications for secondary loops
Learn about the various hardware components that make up the delivery system secondary loop that
provides the chilled, conditioned water to the heat exchanger. The delivery system includes pipes, hoses,
and the required connection hardware to connect the hoses to the heat exchanger. Hose management
can be used in raised-floor and non-raised-floor environments.
The heat exchanger can remove 100% or more of the heat load from an individual rack when it is running
under optimum conditions.
The primary cooling loop is considered to be the building chilled-water supply or a modular chiller unit.
The primary loop must not be used as a direct source of coolant for the heat exchanger.
Procurement and installation of the components that are needed to create the secondary cooling loop
system are required for this design and are your responsibility. The main purpose is to provide examples
of typical methods of secondary loop setup and operating characteristics that are needed to provide an
adequate and safe supply of water to the heat exchanger.
Attention:
The overpressure safety device must meet the following requirements:
• Comply with ISO 4126-1.
• Be installed so that it is easily accessed for inspection, maintenance, and repair.
• Be connected as close as possible to the device that it is intended to protect.
• Be adjustable only with the use of a tool.
• Have a discharge opening that is directed so that discharged water or fluid does not create a
hazard or be directed toward any person.
• Be of adequate discharge capacity to ensure that the maximum working pressure is not
exceeded.
• Be installed without a shutoff valve between the overpressure safety device and the protected
device.
Read the following guidelines before you design the installation:
• A method for monitoring and setting the total flow rate that is delivered to all of the heat exchangers is
required. This can be a discrete flowmeter that is built into the flow loop or a flowmeter within the
secondary loop of the coolant distribution unit (CDU).
• After you set the total flow rate for all of the heat exchangers by using a flowmeter, it is important to
design the plumbing so that it provides the flow rate that you want for each heat exchanger and
provides a way to verify the flow rate. Other methods, such as inline or external flowmeters, can provide
a more accurate method for setting the flow rate through the individual shutoff valves.
Manifolds and piping:
Manifolds that accept large-diameter feed pipes from a pump unit are the preferred method for
splitting the flow of water to smaller-diameter pipes or hoses that are routed to individual heat
exchangers. Manifolds must be constructed of materials that are compatible with the pump unit and
related piping. The manifolds must provide enough connection points to allow a matching number of
supply and return lines to be attached, and the manifolds must match the capacity rating of the
pumps and the loop heat exchanger (between the secondary cooling loop and the building chilled-
water source). Anchor or restrain all manifolds to provide the required support to avoid movement
when quick-connect couplings are connected to the manifolds.
Example of manifold supply pipe sizes:
50 Power Systems: Site and hardware planning