Study On Operation Performance Of The Refrigerant Initiative And Passive Circulating System

Some rooms such as communication base station and computer rooms also need cooling when the outdoor temperature was low in winter and required steady humidity and cleanliness. When the outdoor temperature dropped in winter, the cooling load was reduced, and the life of the compressor greatly shortened due to frequently compressor stopped and started, and it was harmful to the steady of the system. It was an issue worthy of study that how to cooling these rooms stably, effectively and energy-saving. To improve air conditioners in the computer rooms, there was an idea of refrigerant initiative and passive circulation system based on the refrigerant natural circulation system. Through the transformation of the general air conditioners, a refrigerant pump was incorporated in the refrigeration cycle and the compressor was shield at the same time. And the system can change into initiative circulation, passive circulation, compressor circulation three modes.This paper established the model of the thermal parameters of refrigerant R22, the steady-state mathematical simulation model of fin-tube heat exchanger, the state mathematical simulation model of refrigerant initiative and passive circuration system, and developed a simulation software to caculate the the refrigerant initiative and passive circulation system with the programming language VB. The experimental results verified the accuracy of the simulation software and calculation accuracy was in line with the simulation requirements. Based on the results of the simulation software, this paper analyzed the various impact factors on the system performance, including the indoor and outdoor temperature, the amount of system refrigerant filling and the refrigerant mass flow rate, the height between the heat exchangers. When the outdoor temperature was5℃, the indoor temperature was35℃, and the height between the heaters was1.5m, the cooling capacity of the initiative circulation was3.09kW, and it was4.25kW of the passive circulation. On this basis, the control strategy of the system was proposed. To meet the need of the cooling capacity in the room, it changed into initiative circulation when△T>26℃, and changed into passive circulation when20.7℃≤△T≤26℃, and changed into compressor circulation when△T<20.7℃.