带引射器和经济器的CO_2跨临界制冷系统

EJECTOR COMBINED WITH ECONOMIZER ADOPTED IN CO_2 TRANSCRITICAL CYCLE REFRIGERATION SYSTEM

为提高CO2跨临界制冷循环的效率,本文提出一种带引射器和经济器的CO2跨临界循环系统。通过合理设计专用的涡旋式或螺杆式CO2压缩机及中间补气孔,采用经济器可减少CO2跨临界循环的压缩不可逆损失;采用引射器代替节流阀,部分回收工质从高压到低压过程的膨胀功,可增加制冷量。通过热力学分析,确定带引射器和经济器的CO2跨临界循环系统合理的补气压力,可以得到较高的循环效率。在较低蒸发温度下,该系统可以明显降低压缩机的排气温度,有利于系统稳定运行。

To improve the energy efficiency ratio (EER) of the CO2 transcritical refrigeration system, an ejector and an economizer are adopted in the CO2 transcritical cycle system. With carefully designing the CO2 special scroll or screw compressor and their supplementary inlet, adopting an economizer can reduce the irreversible energy loss of CO2 transcritical cycle compression process; adopting an ejector instead of the throttle valve can recover some high-pressure potential power and increase the cooling capacity. Based on thermodynamic analysis on the system, the results show that a favorable EER can be gotten with the reasonable intermediate pressure of the CO2 ejector-economizer transcritical cycle, and a lower discharge temperature of compressor can be obtained especially when the evaporation temperature is low which is favorable for the steady operation of the system.