摘要
为了转移建筑峰值负荷,提出一种CO_(2)水合物蓄冷空调系统,该系统以CO_(2)为循环工质,以CO_(2)水合物为蓄冷介质,采用直接接触式蓄冷方式,可有效减少传热热阻,提高系统性能。基于热力学循环分析方法,对CO_(2)水合物蓄冷系统循环建立数学模型,进行理论分析,结果表明:当CO_(2)消耗量增加到制冷剂质量流量的20%时,系统的性能系数增加到原来的1.25倍。根据温度降低CO_(2)水合物更容易生成的特性,随着蒸发温度的升高,潜热蓄冷量减少,总瞬时蓄冷量和压缩机功耗降低,系统性能系数增大。升高蒸发温度和降低气冷器出口温度有助于提升蓄冷系统的性能。气冷器出口温度对系统的最优排气压力影响较大,而蒸发温度的变化对系统最优排气压力影响较小。当蒸发温度从2℃升高到8℃时,系统的最优排气压力值均维持在8.6 MPa左右。当气冷器出口温度从35℃升高到45℃时,最优排气压力的平均上升幅度约为0.24 MPa/℃。
A novel CO_(2) hydrate-based refrigeration system with cold energy storage is proposed to shift the peak load of buildings.The refrigerant utilized in the system cycle is CO_(2),and CO_(2) hydrate is used as the cold storage medium.The direct contact heat exchange method is applied to the system,which can greatly improve the performance of the unit.A mathematical model of the system was developed based on the thermodynamic analysis method and theoretical analysis was conducted.Results show that when the consumption of CO_(2) increases to 20% of the refrigerant mass flow rate,the coefficient of performance of the system is improved by 1.25 times compared to the original coefficient of performance.Based on the property that CO_(2) hydrates are more likely to be generated at lower temperatures,the latent heat storage capacity decreases as the evaporation temperature increases.Additionally,the total storage capacity and compressor power consumption decrease and the coefficient of performance increases as the evaporation temperature increases.The improvement of system performance can be achieved by increasing the evaporation temperature and reducing the gas cooler outlet temperature.The gas cooler outlet temperature has a greater effect on the optimal discharge pressure of the system,while the change in evaporation temperature has a lesser effect on the optimal discharge pressure of the system.When the evaporation temperature increases from 2 ℃ to 8 ℃,the optimal discharge pressure of the system remains at about 8.6 MPa.When the gas cooler outlet temperature increases from 35 ℃ to 45 ℃,the average increase of the optimal discharge pressure is about 0.24 MPa/℃.
作者
张玉梅
马国远
王磊
ZHANG Yumei;MA Guoyuan;WANG Lei(Faculty of Environment and Life,Beijing University of Technology,Beijing 100124,China)
出处
《北京工业大学学报》
北大核心
2025年第2期121-129,共9页
Journal of Beijing University of Technology
基金
国家重点研发计划资助项目(2022YFC3802501-5)。
关键词
CO_(2)水合物
蓄冷空调
蓄冷介质
直接接触
性能系数
最优排气压力
CO_(2)hydrate
cold storage air conditioning system
cold storage medium
direct contact
coefficient of performance
optimal discharge pressure
作者简介
张玉梅(1995-),女,博士研究生,主要从事制冷与空调系统节能技术方面的研究,E-mail:zhangyumei@emails.bjut.edu.cn;通信作者:王磊(1989-),男,讲师,主要从事储能与冷热能高效利用技术方面的研究,E-mail:wanglei@bjut.edu.cn。
