| With the rapid development of Information Technique and the extensive application of Internet. The Data Center, as one of the critical nodes in information transmission, its function is continuously extended as well as its scale and capacity. Moreover, the energy consumption of the air conditioner is ever increasing when the steep rise of the heat emission density brings the challenges for the maintenance of the Data Center's thermal environment, especially in these early-established data centers. due to the inappropriate layout of the cabinet and the inappropriate air supplying mode of the air-conditioner, it is faced with new challenges from its safety and energy economization.Thesis focuses on the Data Center of Guangzhou University and uses a combined research method of actual measurement and CFD simulation to test and analyze the characteristics and influencing factors of the thermal environment as well as its energy consumption. Furthermore, considering the existing problems of the thermal environment in the Data Center, we have put forward the scheme of molding the air supply mode of the air hose on the cold air box by completely switching off the cold channel. By CFD numerical simulation, we get the effectiveness of this modification scheme and the energy saving properties of the air-conditioner, all of which provide the statistical evidence for improving the thermal environment of the small and medium-sized IDC as well as the research on energy saving measures of the air-conditioner system.The energy consumption monitor result based at Guangzhou University shows that the airconditioner of the Data Center makes up 40 percents of the total energy consumption. The load of the envelope structure occupies about 10 percents of the air-conditioner' s overall load. The energy consumption of the air-conditioner varies with the change of outdoor temperature, and the variation range of its monthly energy consumption is from 18029 kW.h to 26927 kW.h. The energy consumption of the chest-type air-conditioner accounts for the total energy consumption of more than 40 percents. However, the coefficient of the cold energy utilization in the the central air-conditioner and the cabinet-type air-conditioner is 1.09 and 0.66 respectively, which illustrated that the efficiency of the the cabinet-type air-conditioner is inferior to that of the central air-conditioner.The thermal environment test result based on the research object demonstrates that the heat-sources among the cabinets in the Data Center are unevenly distributed. The outlets of the air- conditioner terminal devices are irrational and the “cascading problems” among the cabinets are serious, thus resulting in the serious mixing-up of the cold and hot flow inside the room, such problems as over-heating or over-cooling in part are easy and common to see. The temperature of the cabinet air inlet is rather on the high side, its value is ubiquitously beyond 25 ?, and for most area, the temperature value has been stuck around 26 ?. When the temperature value of the cabinet air inlet reaches 23?, the operating ambient temperature of the IT equipment in the cabinet is more or less beyond 27?. Furthermore, when the temperature difference between the air supply and air return of the air-conditioner is up to 10?, it is far more beyond the required value(4~6?) in specifications.The comparison between the temperature field and the velocity field's measured value and simulated value based on the research object shows 80% of the temperature difference is within 2? and 96% of the velocity difference is below 1.5m/s, which proves that the simulated result is better identical with the measured result and the engineering accuracy of the CFD simulated method is available for reaching the requirement for the macro airflow of the Data Center.The simulated result of this modification scheme shows, the variation range of the air inlet's temperature has decreased from 19?~29? to 22?~23?, the gradient range of the temperature is from 10? to 4?. The temperature of the heat dissipation channel is held from 28 ? which was 23 ? ~ 31 ? before. Therefore, the phenomenon of over-cooling or overheating in part becomes rare to see and the effect for the improvement of the thermal environment is significant. The temperature of the cabinet air inlet is improved from 17.6?(central air-conditioner) and 9.6 ?(cabinet-type air-conditioner) to 22 ?, while the temperature difference of the air supply and air return is decreased from 10? to 6?. Therefore, the cold energy ‘s utilization coefficient of the air conditioner has been improved significantly and the possibility of condensation has also been reduced. In October 2015, the electricity consumption of the air-conditioner system has declined from 26607 k W.h to 20341 kW.h, among which the power consumption of the air conditioner was lowered by 24 percents, and its energy-saving effect is remarkable. |
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