Where Are Fans Used in Data Centers?
Data center fans are used throughout the cooling chain, from indoor
precision cooling equipment to outdoor heat-rejection systems. Different
applications require different combinations of airflow, pressure,
efficiency, control and installation size.
1. CRAC and Precision Air Conditioning
Computer Room Air Conditioning (CRAC) units are widely used to maintain
controlled environmental conditions inside data centers. Fans circulate
conditioned air through the data hall, raised floor, ductwork or
containment system.
Because air must often pass through filters, evaporator coils and other
system resistance, centrifugal fan solutions are commonly used in this
application.
Recommended ebm-papst fan families:
RadiPac, RadiCal and suitable RadiFit centrifugal fan solutions.
2. CRAH Units
Computer Room Air Handler (CRAH) units typically use chilled-water
cooling coils combined with fans to circulate air through the data
center. The fan needs to deliver stable airflow while overcoming the
pressure resistance of the coil, filters and airflow distribution
system.
Variable-speed EC fans allow airflow to respond to changing cooling
loads and system conditions.
Recommended ebm-papst fan families:
RadiPac, RadiCal and other suitable EC centrifugal fan solutions.
3. Data Center FanGrid and Fan Wall
Fan walls and FanGrid systems use multiple fans in parallel to deliver
airflow across a large air-handling section. They can be used in CRAH
units, AHUs and custom data center cooling equipment.
The modular design makes it possible to distribute airflow across the
equipment and implement redundancy strategies when required by the
overall system design.
Recommended ebm-papst fan families:
RadiPac and RadiCal centrifugal fan solutions, with the final
configuration selected according to the equipment design and duty point.
4. In-Row Cooling
In-row cooling places cooling equipment close to server racks, helping
remove heat near high-density IT loads. Because the cooling unit is
installed between or adjacent to racks, available installation space
can be limited.
Fans used in in-row cooling therefore need to balance airflow,
pressure capability, controllability and compact dimensions.
Recommended ebm-papst fan families:
AxiEco 200, RadiCal and DiaForce, depending on the cooling unit design.
5. AHU and Indoor Air Handling Systems
Air Handling Units can form an important part of large data center
cooling systems. They may handle supply air, return air, filtration,
cooling coils and other air-treatment functions.
Fan selection should be based on the complete AHU system curve,
including airflow resistance created by filters, heat exchangers,
dampers and ductwork.
Recommended ebm-papst fan families:
RadiPac, RadiCal and suitable RadiFit centrifugal fan solutions.
6. Rear-Door Heat Exchangers (RDHx)
Rear-door heat exchangers are increasingly used in high-density data
centers. Installed directly behind server racks, an RDHx transfers
heat from server exhaust air to a liquid circuit close to the source.
Depending on the RDHx design, fans can help move air through the heat
exchanger while maintaining a compact rack-level cooling architecture.
Recommended ebm-papst fan families:
RadiCal and AxiEco 200 for suitable RDHx designs.
7. CDU and Liquid Cooling Systems
Liquid cooling is becoming increasingly important for AI servers and
high-density computing. Although liquid cooling can reduce the amount
of air cooling required around high-heat processors, fans can still
play an important role elsewhere in the thermal-management system.
Fan applications can include coolant distribution equipment,
liquid-to-air heat exchangers and facility-level heat-rejection
systems.
Recommended ebm-papst fan family:
RadiPac can be considered for suitable coolant distribution unit
applications, with final selection based on the CDU architecture and
required operating point.
8. Dry Coolers and Fluid Coolers
Dry coolers reject heat from water or water-glycol circuits to outdoor
air. They are particularly relevant to modern data center cooling
architectures because they can form part of both conventional
chilled-water systems and liquid-cooling heat-rejection systems.
These systems commonly use axial fans to move large volumes of ambient
air across heat-exchanger coils.
Recommended ebm-papst fan family:
AxiBlade and other suitable ebm-papst axial fan solutions.
9. Air-Cooled Chillers and Condensers
Air-cooled chillers and condensing units use fans to move outdoor air
through condenser coils and reject heat from the refrigeration system.
These systems may operate across changing outdoor temperatures and
cooling loads.
Axial fan selection should consider the heat exchanger, required
airflow, pressure conditions, acoustic targets and control strategy.
Recommended ebm-papst fan family:
AxiBlade and other suitable EC axial fan solutions.
10. Cooling Towers and Facility Heat Rejection
Cooling towers can form part of the heat-rejection chain in
water-cooled data center plants. Fans move air through the tower to
support heat and mass transfer between circulating water and ambient air.
Cooling tower fan requirements vary significantly according to tower
size and design. ShengRui recommends confirming the existing fan model,
airflow requirement, installation dimensions and operating conditions
before selecting an ebm-papst replacement or alternative solution.
