CO_(2)/HCs混合工质跨临界制冷循环的热力学性能分析  

Thermal performance analysis of CO_(2)/HCs mixture refrigerant transcritical refrigeration cycle

作　　者：杨俊兰 韩一飞 李金芮 YANG Jun-lan;HAN Yi-fei;LI Jin-rui(School of Energy and Safety Engineering,Tianjin Chengjian University,Tianjin 300384,China)

机构地区：[1]天津城建大学能源与安全工程学院,天津300384

出　　处：《化学工程》2022年第6期56-60,共5页Chemical Engineering(China)

基　　金：天津市自然科学基金资助项目(17JCZDJC31400)。

摘　　要：为了分析CO_(2)/HCs混合工质用于单级带膨胀机系统的性能,研究了CO_(2)/R170,CO_(2)/R290,CO_(2)/RE170,CO_(2)/R12704种混合工质的特性,建立单级带膨胀机系统热力学模型,分析了不同混合工质配比对系统性能和高压压力的影响。结果表明:为实现系统跨临界运行,混合工质中HCs的摩尔分数存在上限;对于系统性能,与纯CO_(2)相比,CO_(2)/R1270的最大制冷性能系数COP最高可提升2%,而CO_(2)/R170、CO_(2)/R290以及CO_(2)/RE170则分别降低25%、12%和10%。当高压压力较低时,CO_(2)/R290对系统性能的提升效果最为明显,最高可提升93%。在最优高压压力方面,与纯CO_(2)相比,CO_(2)/R290、CO_(2)/RE170以及CO_(2)/R1270均可降低系统最优高压压力,最大可分别降低13%、10%和7%,而CO_(2)/R170则提升了15%;综合考虑系统性能和降压效果,CO_(2)/R1270和CO_(2)/RE170的综合性能较好,CO_(2)/R290更适用于运行压力较低的设备环境,而CO_(2)/R170综合性能较差。In order to analyze the performance of CO_(2)/HCs mixture refrigerant used in single-stage expander system,the characteristics of CO_(2)/R170,CO_(2)/R290,CO_(2)/RE170 and CO_(2)/R1270 mixed working fluids were studied.The thermodynamic model of single-stage expander system was established,and the effects of different mixing ratios of working fluids on system performance and discharge pressure were analyzed.The results show that in order to realize the transcritical operation of the system,the mole fraction of HCs in the mixture has an upper limit.For system performance,compared with pure CO_(2),the maximum coefficient of performance(COP)of CO_(2)/R1270 can be increased by 2%,while CO_(2)/R170,CO_(2)/R290 and CO_(2)/RE170 are reduced by 25%,12%and 10%,respectively.When the discharge pressure is low,the improvement effect of CO_(2)/R290 on the system performance is the most obvious,up to 93%.In terms of optimal discharge pressure,compared with pure CO_(2),CO_(2)/R290,CO_(2)/RE170 and CO_(2)/R1270 can reduce the optimal discharge pressure of the system,which can be reduced by 13%,10%and 7%,respectively,while CO_(2)/R170 is increased by 15%.Considering the system performance and step-down effect,CO_(2)/R1270 and CO_(2)/RE170 have better comprehensive performance.CO_(2)/R290 is more suitable for the equipment environment with low operating pressure,while CO_(2)/R170 has poor comprehensive performance.

关 键 词：二氧化碳 碳氢化合物 混合制冷剂 跨临界循环 系统性能 

分 类 号：TB61.2[一般工业技术—制冷工程]