Research And Development Of HKF-60FH Refrigeration Unit And Its Application In Data Center

Being typical large-scale, high-density electronic equipment integrated system, thermal load and heat flux density of data center is rising sharply with the development of the modern science and technology. Air conditioning equipment is an important support subsystem of data center. The annual energy consumption of air conditioning equipment is about the total energy consumption’s 35%～45% of the data center, so reducing the energy consumption of air conditioning has become the most important task of energy conservation and emission reduction work. The conveying distance of refrigerant is very close in current domestic and international data center air conditioning system with heat pipe. And the energy consumption is very large when the compression refrigeration system being part of load and other issues, such as, high lubricating oil return problem, and the huge volume of refrigeration unit. Based on the above problems, this paper has done the following works. (1) Analyzing theory research、 experimental and application of heat pipe in data center by collecting data at home and abroad which can provide design ideas and guidance for the experimental. (2) Based on the current situation that a composite refrigeration unit with heat pipe for data center and other electronic equipment has been researched and developed, it is determined to use an integrated refrigeration system with vapor compression and separated heat pipe system. It contains three work modes:vapor compressing refrigeration, composite refrigeration and refrigeration with heat pipe respectively. It can switch working mode according to the temperature difference of indoor and outdoor automatically. Every cooling loop is formed by scroll compressors which two of them are parallel. In this way, the unit can regulate cooling capacity by changing volume of compressors. Heat pipe exchangers and refrigeration condensers in V-shaped array share a fan and assemble a combined heat exchanger by the air-cooled side. Condensers are made of aluminum and adopt parallel flow. (3) The design calculation of the HKF-60FH unit has been carried, including thermodynamic system calculation, condenser and end unit of composite refrigeration unit with heat pipe. And, scroll compressor was selected in vapor compressing refrigeration unit after that. (4) According to test, the refrigeration capacity and COP of vapor compressing refrigeration mode can reach 61.3kW and 3.23W/W when the ambient temperature is 35℃. Furthermore, the capacity and COP of heat pipe mode achieve 59.8kW and 11.3W/W when the ambient temperature is 10℃.60kW composite refrigeration unit with heat pipe is used in high performance computer system and its comprehensive energy efficiency can reach to 7.8. The experiment and application show that the performance of R & D composite refrigeration unit with heat pipe can make full use of the outdoor cold source, so it can reduce the energy consumption substantially. Furthermore its reliable and efficient performance highlights during operation.