超临界CO_2层积式微通道气体冷却器的研究  

Research on the Staked Microchannel Gas Cooler for the Super-critical Carbon Dioxide

作　　者：顾昊翔 李敏霞[1] 王凯建 马一太[1] 

机构地区：[1]天津大学中低温热能高效利用教育部重点实验室,天津300072 [2]浙江微智源能源技术有限公司,杭州311600

出　　处：《机械工程学报》2014年第10期155-162,共8页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(50976075)

摘　　要：以自然工质CO2作为研究对象,对超临界CO2层积式微通道气体冷却器进行研究。在试验研究中,通过改变高压压力和冷却水流量,得到不同工况下的换热量与传热系数,发现换热量随水流量增加而增加,制热能效比(Coefficient of performance,COP)随冷却高压升高而降低。换热器总传热系数可以达到700 W/(m2?K),总换热量可达9 kW。理论分析得出了降低制冷剂测出口温度有利于提升水侧出口温度和COP,故利用有限体积法与TDMA方法结合编制模拟程序,选用合适的换热关联式对微通道气体冷却器进行优化。研究发现增加通道长、水侧水力直径和通道排数,减小通道间距,都能提高水的出水温度,并得到最优结构使出水温度达到60℃以上。Anew staked microchannel heat exchanger is studied as a gas cooler for super-critical CO2.Through the experiments,by changing the inlet pressure of CO2 and mass flow rates of water,the capacity of heat transfer and the total heat transfer coefficient of this gas cooler are obtained in different conditions.The heat transfer capacity goes up with the mass flow rate of water and the coefficient of performance（COP） goes down with the increasing of inlet pressure of CO2.The heat transfer coefficient reaches 700 W/（m2· K） while the heat transfer capacity reaches 9 kW.By using finite volume method（FVM） and TDMA method in the simulation program,the heat transfer process of the gas cooler is simulated for the conclusion that decreasing the outlet temperature of carbon dioxide benefit the increase of outlet temperature of water side and the COP.During the simulation,the proper correlations of both water and carbon dioxide are selected.The simulation deviation is small enough.The microchannel gas cooler is optimized with the program by calculating the heat transfer coefficient and heat transfer capacity.It is found that the outlet temperature of water can be increased by reducing the distance of channels of both side and increasing the rows of channels,as well as increasing the hydraulic diameter of water side and the row of channels.The optimized construction is obtained based on regulations,which lead the outlet temperature of water side to above 60 ℃.

关 键 词：超临界 CO2 微通道 气体冷却器 优化 

分 类 号：TK124[动力工程及工程热物理—工程热物理]