| 摘要: |
| 为提高CO2系统用于建筑全年空间供热供冷的性能，本文提出集成引射器与机械过冷的跨临界CO2冷热联供系统（EJ-DMS）。通过构建系统的热力学模型，以性能系数（COP）为目标函数，采用遗传算法对排气压力和过冷度进行优化，并对系统应用于5个典型城市的能耗、全年性能系数（COPann）进行场景分析。结果表明：EJ-DMS相比常规机械过冷系统、常规引射系统，COP在制热和制冷模式下分别提高10.90%、5.58%和8.99%、18.12%，COPann分别提高7.95%和5.98%。EJ-DMS相比常规引射系统在制热和制冷模式下排气压力分别降低0.47 MPa和0.77 MPa。此外，EJ-DMS系统在广州和哈尔滨运行时的COPann提升率最大，表明其更适合环境温度较高或较低的地区，如夏热冬暖和严寒地区。本文可为CO2冷热联供系统的构建和优化提供理论参考。 |
| 关键词: 自然工质CO2 冷热联供 引射器 机械过冷 COP |
| DOI： |
| Received:January 04, 2023Revised:February 21, 2023 |
| 基金项目:国家重点研发计划(2021YFE0116100),天津市研究生科研创新项目( 2022SKYZ207) 资
助。 |
|
| Performance Analysis of CO2 Systems Integrated with Ejector and Dedicated Mechanical Subcooling |
|
Dai Baomin, Zhao Ruirui, Liu Shengchun, Qian Jiabao, Xu Tianyahui, Liu Chen, Yang Peifang
|
| (Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce) |
| Abstract: |
| A transcritical CO2 system combined with an ejector and dedicated mechanical subcooling (EJ-DMS) was developed to improve the performance of the CO2 system in the space heating and cooling of buildings throughout the year. A thermodynamic model of the system was devised. Then, the discharge pressure and subcooling degree were optimized using a genetic algorithm by considering the coefficient of performance (COP) as the objective function. Using five typical cities as application scenarios, the energy consumption and annual performance factor (COPann) of the system were analyzed. The results show that, compared with a conventional mechanical subcooling system and the conventional ejector system, the heating COP of EJ-DMS is enhanced by 10.90% and 5.58%, respectively, and the cooling COP is increased by 8.99% and 18.12%, respectively. The COPann values are improved by 7.95% and 5.98%, respectively. Compared with the conventional ejector system, the discharge pressure of EJ-DMS is reduced by 0.47 MPa and 0.77 MPa in the heating and cooling modes, respectively. In addition, the COPann improvement ratio of the EJ-DMS system is the highest when operating in Guangzhou and Harbin, indicating that the EJ-DMS system is more suitable for regions with relatively high or low ambient temperatures, such as hot summer and warm winter or severely cold regions. This study provides a theoretical reference for the development and optimization of a combined cooling and heating CO2 system. |
| Key words: natural working fluid CO2 combined cooling and heating ejector mechanical subcooling COP |
