该文将真空管集热器与直膨式太阳能热泵结合,提出一种真空管直膨式太阳能热泵系统。实验研究典型工况下太阳辐照度、循环水温度对系统性能的影响,并探讨压缩机变频条件下系统的动态性能。结果表明,提高太阳辐照度、降低循环水温度有利于提高系统性能,在太阳辐照度为850 W/m2,循环水温度为55 ℃时系统取得最大COP,为5.36。压缩机频率为42 Hz的系统COP为4.08,较45、47、50 Hz分别提高1.23%、8.5%、13.6%。
Abstract
Based on the annular vacuum of vacuum tube collector can suppress the convective heat loss around the heat absorber, which can achieve higher collector temperature and collector efficiency compared with traditiona flat plate collector, this paper proposed an evacuated tube type direct-expansion solar-assisted heat pump, which combines evacuated tube collector with direct expansion solar heat pump. This paper experimentally investigates the effects of solar radiation intensity and circulating water temperature on system performance under typical operating conditions, and explores the dynamic performance of the system under the condition of compressor frequency conversion. The results show that increasing solar radiation intensity and decreasing circulating water temperature are beneficial to improve the system performance. The system achieves the maximum COP of 5.36 at the radiation intensity of 850 W/m2 and circulating water temperature of 55 ℃. The COP of the system with the compressor frequency of 42 Hz is 4.08, which is 1.23%, 8.5% and 13.6% higher than that of 45, 47 and 50 Hz, respectively.
关键词
热泵系统 /
太阳能集热器 /
性能系数 /
直膨式 /
真空管 /
变频压缩
Key words
heat pump systems /
solar collectors /
coefficient of performance /
direct-expansion /
evacuated tube /
variable frequency
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