Research On Performance Of Fixed Dehumidifying Bed Driven By Multiple Energy And Its Application In Data Center Air Conditioning

With the expansion of the scale of data centers around the world,the problems of high energy consumption and high heat density in data centers have been paid more and more attention.The energy consumption of the air-conditioning system accounts for about 40% of the total energy consumption of data centers.With ensuring the normal operation of the IT equipment in data centers,reducing the energy consumption of the air-conditioning system is of great significance to improve the energy efficiency of data centers.The temperature and humidity independent control air-conditioning system based on solid adsorption dehumidification and dew point evaporative cooling can effectively solve above problems.Since the main energy consumption of this system is regeneration energy,the reasonable selection and combination of heat sources for regeneration is particularly crucial.In order to achieve energy-saving and efficient dehumidification/regeneration process,a series of experimental and theoretical research on the performance of fixed dehumidifying bed driven by multiple energy sources are carried out,and the energy efficiency of the dew point cooling system in data centers based on the fixed dehumidifying bed is analyzed and evaluated.First of all,from the point of multi-energy-driven regeneration,experiments on dehumidification and regeneration driven by microwave and solar radiation is developed respectively to improve the energy efficiency and reduce as much energy consumption as possible,based on which the kinetic model is established.Considering the high exhaust air temperature and rich waste heat resources of data centers,the combination of heat sources for regeneration is optimized,then the regeneration process driven by solar energy and hot air is proposed.On the basic of this,the operation mode of fixed dehumidifying bed is improved,the desiccant material is optimized,the dehumidification/regeneration cycle system driven by coupling of solar energy and hot air is constructed,and the heat and mass transfer model of this system is established.With numerical simulation study,the operation performance of this system under different working conditions are compared and analyzed,including inlet air conditions,solar radiation intensity,length of desiccant layer and working mode swapping time,which provides a basis for system optimization.Finally,a data center dew point cooling system based on fixed dehumidifying bed is designed,in which the regeneration process is driven by multiple energy sources such as the return air of hot aisles in data centers,solar energy and microwave.According to different working conditions,the coupling and complementarity form of multiple energy sources for regeneration is developed,the design and selection of main equipment of this system is completed,and the mathematical model of this system is established.With numerical simulation,the energy efficiency of this system under summer conditions of six cities in China is compared and analyzed.The results show that compared with the vapor compression system,the energy saving effect of this system is obvious,therefore it has broad application prospects in data center cooling.