中文摘要：

对双级压缩系统中间冷却器从理论上分析了带中间冷却器的双级压缩循环的性能规律.在给定的蒸发温度和气体冷却器出口温度下,系统存在最优的压缩机排气压力使得性能最优;同时在每一个压缩机排气压力下,也存在最优的中间压力使得系统性能最优;对比选择超临界CO2和亚临界CO2在管外、管内的换热及压降关联式,设计和模拟中间冷却器.建立带中间冷却器的双级压缩系统,通过实验探索此种双级压缩系统的规律,验证了带中间冷却器双级压缩系统最优压缩机排气压力和最优中间压力的存在以及在提高CO2跨临界循环性能的作用.利用自行设计的中间冷却器,在实验工况下,系统制冷性能系数可达2.5,制热性能系数为3.5.

英文摘要：

The performance of two-stage compression system with inter-stage cooler was studied theoretically.At the given evaporating temperature and outlet temperature of gas cooler,there exists an optimum discharge pressure of compressor,leading to the optimum performance.Meanwhile,under each discharge pressure of compressor,there also exists an optimum intermediate pressure.The inter-stage cooler was designed and simulated with the selected heat transfer and pressure drop correlation of super-critical and sub-critical CO2 in or out of tube.A two-stage compression system with inter-stage cooler was established to study the rules of this system.The experimental results indicate that the two-stage compression system with inter-stage cooler has the optimum compressor discharge pressure and the op-timum intermediate pressure,and that it can also improve the performance of CO2 trans-critical system.By using the self-designed inter-stage cooler,the COP can reach 2.5 and COPh 3.5 under the experimental condition.