TY - JOUR
T1 - Exergy and energy analysis of a double evaporating temperature chiller
AU - Zhang, Kai
AU - Zhu, Yutong
AU - Liu, Jinxiang
AU - Niu, Xiaofeng
AU - Yuan, Xiaolei
N1 - Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2018/4/15
Y1 - 2018/4/15
N2 - Temperature and humidity independent control (THIC) has been demonstrated as an effective way to improve the performance for air-conditioning systems. As an alternative option of THIC method, a double evaporating temperature (DET) chiller using zeotropic mixture refrigerants of R32 and R236fa has been proposed to substitute the traditional water-cooled chiller. The low temperature chilled water of 7 °C and high temperature chilled water of 17 °C will be produced simultaneously by this DET chiller, and the latent and sensible cooling loads of buildings can be afforded by the produced low temperature chilled water and high temperature chilled water respectively. In this paper, the experiments with different concentration ratios of R32 to R236fa are carried out on a 4.0-kW DET chiller. To further improve the energy performance of the DET chiller, the exergy analysis is used to investigate the effects of chilled water temperature and mass concentration of zeotropic mixture on the DET chiller. The exergy loss for each component is discussed in detail to identify the inefficient components, and then indicate the ways to improve the performance of DET chiller. The results show that the DET chiller achieves the lowest exergy loss and highest exergy efficiency when the mass concentration ratio of R32 to R236fa is 40%: 60%. Furthermore, the design temperature of high temperature chilled water should be at 16 °C to improve the energy utilization of DET chiller. This study will help to understand the design and operation for the DET chiller based air-conditioning systems.
AB - Temperature and humidity independent control (THIC) has been demonstrated as an effective way to improve the performance for air-conditioning systems. As an alternative option of THIC method, a double evaporating temperature (DET) chiller using zeotropic mixture refrigerants of R32 and R236fa has been proposed to substitute the traditional water-cooled chiller. The low temperature chilled water of 7 °C and high temperature chilled water of 17 °C will be produced simultaneously by this DET chiller, and the latent and sensible cooling loads of buildings can be afforded by the produced low temperature chilled water and high temperature chilled water respectively. In this paper, the experiments with different concentration ratios of R32 to R236fa are carried out on a 4.0-kW DET chiller. To further improve the energy performance of the DET chiller, the exergy analysis is used to investigate the effects of chilled water temperature and mass concentration of zeotropic mixture on the DET chiller. The exergy loss for each component is discussed in detail to identify the inefficient components, and then indicate the ways to improve the performance of DET chiller. The results show that the DET chiller achieves the lowest exergy loss and highest exergy efficiency when the mass concentration ratio of R32 to R236fa is 40%: 60%. Furthermore, the design temperature of high temperature chilled water should be at 16 °C to improve the energy utilization of DET chiller. This study will help to understand the design and operation for the DET chiller based air-conditioning systems.
KW - Double evaporating temperature
KW - Exergy analysis
KW - Temperature and humidity independent control
KW - Zeotropic mixture refrigerant
UR - http://www.scopus.com/inward/record.url?scp=85039975494&partnerID=8YFLogxK
U2 - 10.1016/j.enbuild.2017.12.055
DO - 10.1016/j.enbuild.2017.12.055
M3 - 文章
AN - SCOPUS:85039975494
SN - 0378-7788
VL - 165
SP - 464
EP - 471
JO - Energy and Buildings
JF - Energy and Buildings
ER -