摘要
针对电热开水机耗电量较大的问题,课题组对基于R744(二氧化碳)工质的超临界热泵开水机进行结构和性能研究。分别针对25℃以上的高温环境、5~25℃的中温环境和-25~5℃的低温环境,给出R744超临界热泵开水机的适宜结构和较佳运行参数;当环境温度高于25℃时,提出采用带预热器的单级压缩结构;当环境温度在5~25℃时,提出采用不带预热器的单级压缩结构;当环境温度低于5℃时,提出采用带级间冷却器的双级压缩结构;计算分析了不同环境温度时系统的耗电量、加热器内的热泵工质与水之间的传热温差分布。应用R744超临界高温热泵模拟软件SCHPSim分析表明:当环境温度分别为30,15和-10℃时,在对应适宜结构的R744超临界热泵开水机情况下,与电热开水机的耗电量比约为1.0∶4.1,1.0∶3.7和1.0∶2.0,具有显著的节能优势,且加热器内R744与水的最小传热温差都在4℃以上,可以保证较高的传热速率。
Aiming at the problem of large power consumption of electric water boiler,the structure and performance of supercritical heat pump water boiler based on R744(carbon dioxide)were studied.For the high environment temperature above 25℃,the medium environment temperature of 5℃to 25℃,and the low environment temperature of-25℃to 5℃,the suitable structure and optimal operating parameters of R744 supercritical heat pump water boiler were given.A single-stage compression structure with a preheater was proposed for membership degree.It shows that when the environment temperature was higher than 25℃,the system could adopt a single-stage compression structure with a preheater,when the environment temperature was 5℃to 25℃,the system could adopt a single-stage compression structure without a preheater,and when the environment temperature was lower than 5℃,the system could adopt a double-stage compression structure with an interstage cooler;the system of coefficient of performance and the heat transfer temperature difference distribution between the heat pump working fluid and the water in the heater were calculated and analyzed in different environment temperature.Systematic analysis was carried out based on the R744 supercritical high-temperature heat pump simulation software SCHPSim.The resault shows that when the environment temperature is 30,15 or-10℃,the power consumption is about 1.0∶4.1,1.0∶3.7,1.0∶2.0 of the electric water boiler in the corresponding structure of R744 supercritical heat pump water boiler situation,which had significant energy-saving advantages.The minimum heat transfer temperature difference between the R744 and the water in the heater is above 4℃,which can ensure a high heat transfer rate.
作者
文鑫
谢继红
宋鑫宇
刘明权
陈雨
WEN Xin;XIE Jihong*;SONG Xinyu;LIU Mingquan;CHEN Yu(College of Mechanical Engineering,Tianjin U niversily of Science&Teehnology,Tianjin 300222,China)
出处
《轻工机械》
CAS
2024年第2期81-85,共5页
Light Industry Machinery
