The Research And Optimization About Cooling System Solutions Of Large Data Center

The article analyses the key factors and current conditions of large data centers and constructs a building model supporting by DeST on the scales of 2000 server racks in 1^stt phase and 2500 server racks in 2^nd phase.And three types of cooling solutions,that is,district cooling compound free cooling,compression chilling compound with free cooling and compression chilling with condensation heats recovery systems,are investigated,for the DC models in five representative cities from different climate areas,which are Harbin,Beijing,Chongqing,Kunming,Guangzhou.The mathematical simulated models for the systems are given in the articles for performance optimization and the cold water temperature case are decided where the inlet water temperature is 12?and outlet water temperature is 18?so that the free cooling module can operate for a longer time.Since the unit types and equipment design indexed are basically selected,the hourly power and total energy consumptions of all solutions and average PUE values of DCs in every city are calculated by MATLAB as well as the economic index including operation costs and annual cost values.It shows that the district cooling compound with free cooling system takes huge advantages both on energy-saving and economic aspects with annual primary energy saving 63.1%and annual costs values decreasing 39.76%over the compression chilling compound with free cooling system.Meanwhile,the compression chilling compound with heat recovery system are huge power-consumption one but also own large potential of waste heat recovery usage.Therefore,the condensation heat and cold water waste heat recovery compound water-source heat pump heating systems are proposed.Aimed at most energy-saving and Beijing taken as example,the inlet cooling water temperature of the condensation heat recovery compound heating system is under discussion in the changing interval of 26?to 37?,and the result reflects that the 37?is the best choice for the system efficient operation after comparing the annual primary energy saving amounts during the heating season.By the same means,the best arrangement of cold water temperature solution for the cold water heat recovery compound heating system is discussed in the interval of 12?to 18?.It shows no obvious varieties as the result from the growing cold water temperatures among the primary energy consumptions/replacements/savings data.Both of the condensation heat and cold water waste heat recovery compound water-source heat pump heating systems are highly energy-saving,however,they are much less non-economic than the solutions with free cooling module.The article continues to investigate the affects when the power price and heat price for sale changes per 10%and finds out that the power price effects the economic level of the system most.The heat recovery compound heating systems becomes much more competitive in economy when the power price goes down about 40%in the case.