| With the development of emerging industries such as artificial intelligence and cloud computing,the application scale of China’s data cente rs has expanded to more than 550,000,followed by the problem of high energy consumption.Among them,the energy consumption of the traditional cooling system accounts for more than 30% of the total energy consumption of the data center.In order to reduce the energy consumption of the cooling system,the researcher proposed a rack level water-cooled separated heat pipe system suitable for large-scale and medium-scale data centers,and studied its thermal performance under full load and standard airflow rat e.However,the average load rate of China’s data centers is only 50.61%.In order to red uce the operation energy consumption of the data centers,the separated heat pipe cooling system will reduce the fan speed according to the actual load,resulting in t he attenuation of heat transfer performance.Therefore,it is very important to study and analyze the heat transfer performance of the separated microchannel heat pipe under low airflow and heating load.Therefore,this paper studies and analyzes the heat transfer performance of the water-cooled separated microchannel heat pipe under low airflow rate by means of experiment and simulation.The contents are as follows:(1)Based on the enthalpy difference laboratory,the experimental table of flow heat transfer of water-cooled separated microchannel heat pipe system was built.The optimal filling ratio of water-cooled separated microchannel heat pipe system is65%.And filling ratio in the experimental analysis of the water separated under low airflow rate microchannel on heat transfer characteristics of the heat pipe system,the results showed that under low airflow rate,the microchannel heat pipe can’t start,but the internal refrigerant can still relatively steady flow,the evaporator exhaust temperature is lower than data center design specification(GB50174-2017)under the regulation of A1 grade computer room air conditioning air supply recommended temperature limit.Therefore,reducing airflow rate is an effective and safe way to save energy when the cabinet is under low load.(2)Based on the obtained experimental data,a steady-state heat transfer model was established for predicting the heat transfer performance of the water-cooled separated microchannel heat pipe system at low airflow rate.The accuracy o f the model is verified by comparing the predicted results with the experiment results.T he maximum average relative error of the result predicted by the established model was6.3%。(3)Based on the one-dimensional steady-state model established,the influence of the operating parameters such as the exhaust temperature of the server,the chilled water supply temperature,the chilled water flow rate,the difference in the height of the evaporator and the condenser on the heat transfer performance at low airfl ow rate is studied and analyzed,and Suggestions are provided for the optimization of these parameters.This research give a guidance to improve the design optimization and energy-saving operation of the application of MCSHP in data center. |
