Figure 1: Rack rear fans.
With the rapid development of Internet technology, data centers are becoming larger and larger. In order to meet the
growing data processing needs, the energy consumption of data centers is also increasing. Therefore, reducing data
center energy consumption and improving energy utilization efficiency have become an important research direction in
the data center industry.
At present, the mainstream data center cooling methods are mainly divided into two types: air cooling system and
liquid cooling system. This article will provide a detailed introduction to the data center air cooling system,
including the basic principles, key technologies, advantages and disadvantages, application scenarios, etc. of the
air cooling system.
1. Basic Principles of Air Cooling System
As the name suggests, air cooling systems are a way of cooling data centers through air. The basic principle is to
use the low-temperature air from the external environment and transport the cold air to the interior of the data
center through fans to cool the equipment.
In data centers, air cooling systems are crucial for maintaining optimal operating temperatures and preventing
equipment overheating. The basic principles of air cooling systems in data centers are similar to those in general
air cooling systems, but with some specific considerations. Here are the key principles:
1. Airflow Management: Data centers require careful airflow management to ensure efficient cooling.
Hot air generated by servers and other equipment needs to be effectively removed, while cool air must be supplied to
the equipment. This is typically achieved through a combination of raised floors, hot and cold aisles, and carefully
positioned vents and fans. Cold air is supplied from the front of the racks, and hot air is expelled from the back.
Figure 2: Computer room airflow diagram.
2. Hot Aisle/Cold Aisle Configuration: In the hot aisle/cold aisle layout, server racks are
organized in alternating rows. The front of the servers faces the cold aisle, where cool air is supplied, while the
rear of the servers faces the hot aisle, where hot air is expelled. This configuration helps to minimize the mixing
of hot and cold air, improving cooling efficiency.
3. Precision Air Conditioning: Data centers often use precision air conditioning systems, which are
specialized cooling units designed to provide precise temperature and humidity control. These units are capable of
delivering cool air directly to the equipment and removing hot air efficiently.
4. Raised Floors: Raised floors are commonly found in data centers and allow for the distribution
of cool air through an underfloor plenum. The cold air is then directed to the front of the server racks, ensuring
proper cooling. Additionally, raised floors provide space for cable management and infrastructure, reducing clutter
and improving airflow.
5. Hot/Cold Aisle Containment: To further enhance cooling efficiency, data centers may implement
hot/cold aisle containment systems. These systems use physical barriers, such as doors or curtains, to separate the
hot and cold aisles, preventing the mixing of air. Containment helps to optimize airflow and improve cooling
effectiveness.
6. Redundancy and Backup: Data centers often incorporate redundant cooling systems to ensure
uninterrupted cooling in case of equipment failure or maintenance. Backup cooling systems, such as additional air
conditioning units or liquid cooling solutions, may be deployed to provide emergency cooling if the primary system
fails.
7. Monitoring and Control: Data centers employ sophisticated monitoring and control systems to
continuously monitor temperature, humidity, airflow, and other environmental parameters. These systems provide
real-time data for optimizing cooling efficiency and early detection of any anomalies or issues.
These principles, along with advanced cooling technologies and best practices, are essential for maintaining a
stable and cool environment in data centers, preventing equipment failures and ensuring the reliable operation of
critical IT infrastructure.
Figure 3: Computer room precision air conditioner.
2. Key Technologies of Air Cooling System
2.1. Fan Technology
The fan is the core component of the air cooling system, and its performance directly affects the cooling effect. Currently, there are two main types of fans on the market: axial fans and centrifugal fans. Axial fans have the advantages of low noise, high efficiency, and long life, and are suitable for large data centers; centrifugal fans have the advantages of small size, low noise, and high energy efficiency, and are suitable for small data centers.
2.2 Heat Exchanger Technology
Heat exchanger is a key component for heat transfer in air cooling systems. At present, common heat exchangers on the market include flat plate heat exchangers, spiral heat exchangers and vortex heat exchangers. Different types of heat exchangers have different heat transfer effects and performance characteristics, and it is necessary to select them according to actual application scenarios.
2.3 Control System Technology
The control system is the adjustment center of the air cooling system, responsible for real-time monitoring and adjustment of fan speed, heat exchanger temperature and other parameters to ensure the stability of the cooling effect. Currently, common control systems on the market include analog control, digital control, artificial intelligence control, etc. Different types of control systems have different control accuracy and response speeds, and they need to be selected based on actual application scenarios.
3. Advantages and Disadvantages of Air Cooling System
The advantages of air-cooled systems are that they are lower cost, easier to maintain and manage, and do not require
additional water resources. In addition, because of its ease of operation, air cooling systems are often used in
small data centers or in applications that require rapid deployment.
However, air-cooled systems also have some disadvantages. First, it requires a large amount of electricity to drive
the fan, resulting in energy waste and increased operating costs. Secondly, because air-cooled systems rely on air
movement, their efficiency will be affected in high-temperature environments. Finally, air-cooling systems can
negatively impact the data center environment by generating large amounts of noise and dust.
Figure 4: Cabinet cooling fans.
4. Application of Air Cooling System
Air cooling systems are widely used in data centers of all sizes, especially those with higher energy consumption requirements. The following are some typical air cooling system application scenarios:
4.1 Large Data Center
Large data centers usually have a large number of server equipment and network equipment, which require a large amount of energy for cooling. The air cooling system can effectively reduce the operating temperature of these devices and improve the operating efficiency of the equipment, thus reducing the energy consumption of the entire data center.
4.2 High-Density Server Room
High-density server rooms usually adopt a densely arranged layout of server equipment, which requires large heat dissipation. The air cooling system can achieve effective heat distribution and ensure the normal operation of the equipment by properly designing the fan layout and heat exchanger layout.
Figure 5: High density data center.
4.3 Power Industry Data Center
Data centers in the power industry need to process large amounts of power data in real time and have high requirements for equipment stability. The air cooling system can effectively reduce the operating temperature of the equipment, improve the stability of the equipment, and ensure the normal operation of the power system.
4.4 Internet Enterprise Data Center
The data centers of Internet companies usually have high business continuity requirements and it is needed to ensure the continuous operation of equipment. The air cooling system can quickly respond and adjust the working status of the cooling equipment to ensure the stable operation of the equipment and meet the business needs of the enterprise.
5. Conclusion
Through reading the detailed introduction of the basic principles, key technologies, application scenarios, etc. of the air-cooling system, we believe that you have a deeper understanding of the air-cooling system. In the future development process, the air cooling system will continue to be optimized and improved to provide better cooling services for data centers.
