System design, control strategy development and performance comparison analysis for a novel air-liquid hybrid data center cooling system based on cold plates.

Data centers are important basic buildings in the era of information technology. In recent years, the number of data centers has been expanding, and among them the refrigeration systems occupy most of the energy. In order to achieve energy savings and carbon reduction, relevant researchers developed various forms of data center cooling systems. Among them, the cooling system based on cold plates has many advantages, such as good heat transfer efficiency, low energy consumption, strong safety and so on, thus becoming the focus of research in the industry. The refrigeration systems based on cold plates contain both liquid-cooled systems and air-cooled systems. However, the conventional systems do not link the two systems, which results in wasted energy. Therefore, this paper innovatively develops a novel air-liquid hybrid data center cooling system based on cold plates that links air-cooled and liquid-cooled. This new system has three modes, which can achieve energy savings and expand the operating range through mode transformation in different scenarios. In addition, this paper also gives the calculation process of the mode switching temperatures and the maximum operating temperature of the new system, and analyzes the energy-saving effect of the new system from the thermodynamic point of view. The results show that the new system proposed in this paper shows excellent energy-saving cost-reduction effects in different types of climate regions compared with the conventional system. Under LM, Harbin achieves the highest energy savings at 22.9 %, while Shenzhen demonstrates the greatest cost reduction rate, reaching 26.7 %. This paper provides a new idea for the construction of data center cooling systems based on cold plates.