Research On The Rack Cooling System Based On The Heat Pipe Backplate In Data Centers

With the continuous development and expansion of Internet users,the heat dissipation in data centers continues to grow.The traditional data center room-level cooling methods can no longer meet the heat dissipation requirements of high heat density data centers,due to the unreasonable airflow organization,local hot spots and the large energy consumption.The cabinet-grade cooling method based on the heat pipe back plate can solve the heat dissipation problem of the high heat density cabinet.Firstly,the thermal performance of the microchannel heat pipe backplane for a cabinet refrigeration system is investigated by experimental study.The experimental results show that the optimal liquid fill rate for the system under standard conditions is between 65%and 75%.At this time,the system obtains the maximum heat exchange amount.On the optimal liquid filling rate condition,the amount of system heat transfer,air side pressure drop and refrigerant mass flow rate increase rapidly as the air flow rate of the evaporating section increases,while the outlet air temperature and the return water temperature increase slowly.As the temperature increases,the heat transfer,outlet air temperature,and outlet water temperature increase gradually.As the inlet water temperature increases,the amount of system heat transfer gradually decreases,and the outlet air temperature and return water temperature gradually increase.Secondly,the steady-state heat transfer model of the heat pipe backplane system is established by the s-NTU method.Comparing the experimental data with the calculated value,the average error is within 10%.Then the model is used to simulate and analyze the flow and heat transfer performance on the refrigerant side of the microchannel backplane system and the optimization of the air side structural parameter considering the system design.Finally,a CFD simulation study was performed on the thermal environment inside the cabinet based on the heat pipe back plate.The influence of server power,circulating air volume,and fan failure at different locations on the thermal environment of the cabinet were analyzed,respectively.Taking the faulty of a fan into consideration distinctively,the emergency measures to increase the fan air volume around the fault location were proposed.The research results show that the server power and the circulating air volume of the rack have a great influence on the thermal environment within the cabinet.To obtain a thermal environment that is suitable for the server operation,it is recommended to place the server with a large power in the middle and lower parts.The maximum power of the cabinet should be rated on the power range of the heat pipe backplate.Because simply increasing the air volume will not significantly improve the thermal environment inside the cabinet.However,it will increase the energy consumption of the fan.Consequently,the fans should be properly selected.The higher the position of the faulty fan is,the larger the local temperature rise is,and the more uneven the temperature in the cabinet is.The more the air volume of the fan around the fault fan increases,the better the improvement of the thermal environment inside the cabinet is.When the air volume increases by 45%,the maximum temperature drop of the server reaches about 10%.