CO_(2)跨临界热泵系统采暖工况下能效和经济对比分析  

Comparative analysis of energy efficiency and economy of CO_(2)transcritical heat pump system under heating condition

作　　者：刘雪涛 李敏霞[1] 马一太[1] 姚良 詹浩淼 LIU Xuetao;LI Minxia;MA Yitai;YAO Liang;ZHAN Haomiao(Low and Medium Grade Energy of Ministry of Education,Tianjin University,Tianjin 300350,China)

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300350

出　　处：《化工进展》2021年第3期1315-1324,共10页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金(51876135);空调设备及系统运行节能国家重点实验室开放基金(ACSKL2018KT02)。

摘　　要：为提高CO_(2)跨临界热泵采暖系统的性能,提出了双级压缩双气冷器中间补气回热系统。结合其他3种CO_(2)热泵系统和R134a单级压缩回热系统,通过建立热力学模型,分析各因素对系统能效的影响。此外,通过构建综合考虑初始投资成本和年运行成本的经济性评价模型,结合典型年气象参数,研究不同城市中各系统在运行周期内的总投资情况。结果表明,CO_(2)热泵系统中,双级压缩双气冷器中间补气回热系统最优COP_(h)最高且可以超过R134a单级压缩回热系统,在环境温度为0℃、出水/回水温度为65℃/40℃时,理论性能系数(COP_(h))可达2.58,比R134a系统高9.1%,比CO_(2)单级压缩系统高22.5%,且排气温度不超过现有压缩机排气温度极限,是能效最优系统。在选定样本城市中,热泵系统运行周期内的总投资成本在上海最低,而在沈阳最高,可见总投资成本受气候区域影响较大。由于CO_(2)压缩机成本过高,CO_(2)热泵系统的总投资成本高于R134a系统。随着CO_(2)热泵技术的提高和生产规模的扩大,当压缩机成本降低80%,CO_(2)双级压缩双气冷器中间补气回热系统的总投资成本将低于R134a系统。In order to improve the performance of the CO_(2)transcritical heat pump heating system,a heat recovery system with secondary air supply for two-stage compression and double gas cooler is proposed.Through the establishment of the thermodynamic model,the impact of various factors on the energy efficiency of the system is analyzed combined with the other three CO_(2)heat pump systems and the R134a single-stage compression regenerative system.In addition,the total investment situation of each system in different cities during the operating cycle is studied based on typical annual meteorological parameters by an economic evaluation model,which comprehensively considers the initial investment cost and annual operating cost.The results show that the heat recovery system with secondary air supply for two-stage compression and double gas cooler is the optimal system scheme,which has the highest COP_(h)and exceeds that of R134a single-stage compression regenerative system.When the ambient temperature is 0℃and the temperature of outlet/return water is 65℃/40℃,the theoretical COP_(h) can reach 2.58,which is 9.1%higher than that of the R134a system,and 22.5%higher than that of CO_(2)single-stage compression system,and the compressor discharge temperature doesn't exceed the existing temperature limit.In the selected sampling cities,the total investment cost of all heat pump systems during the operating cycle is the lowest in Shanghai and the highest in Shenyang,which shows that it is greatly affected by the climate region.Due to the high cost of the CO_(2)compressor,the total investment cost of the CO_(2)heat pump system is higher than that of the R134a system.With the improvement of CO_(2)heat pump technology and the expansion of production scale,when the cost of the compressor is reduced by 80%,the total investment cost of the heat recovery system with secondary air supply for two-stage compression and double gas cooler will be lower than that of R134a system.

关 键 词：CO_(2)热泵 跨临界 采暖 能效 经济 

分 类 号：TK124[动力工程及工程热物理—工程热物理]