TY - JOUR
T1 - Boiling flow patterns and dry-out characteristics of R-1234ze(E) in a plate heat exchanger
AU - Lee, Dong Chan
AU - Jo, Chang Uk
AU - Kim, Byeongsu
AU - Kim, Yongchan
N1 - Funding Information:
This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korean Government Ministry of Trade, Industry, and Energy (Grant No. 20172010105890).
Publisher Copyright:
© 2020
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/11
Y1 - 2020/11
N2 - In this study, boiling flow patterns and dry-out characteristics of R-1234ze(E) in a plate heat exchanger (PHE) are investigated through visualizations and surface temperature measurements. The boiling flow patterns in the PHE are classified into three regimes by reflecting an evident flow direction and intermittent flooding (IF): rough liquid film flow, pulsating annular flow, and steady annular flow. Boiling mechanisms in the liquid-preferred and vapor-preferred paths are analyzed in a single channel. A boiling flow pattern map of R-1234ze(E) in the PHE is developed in terms of liquid and vapor superficial momentums, and the criteria for the transitions of the flow regimes are proposed to provide a reference for predicting flow characteristics during phase changes. Based on the measured surface temperatures, the partial dry-out is observed at medium to high vapor qualities in the center of the vapor-preferred path owing to the lack of the liquid phase. In addition, the relationships between the IF, partial dry-out, and heat transfer coefficients are comprehensively analyzed with physical interpretations.
AB - In this study, boiling flow patterns and dry-out characteristics of R-1234ze(E) in a plate heat exchanger (PHE) are investigated through visualizations and surface temperature measurements. The boiling flow patterns in the PHE are classified into three regimes by reflecting an evident flow direction and intermittent flooding (IF): rough liquid film flow, pulsating annular flow, and steady annular flow. Boiling mechanisms in the liquid-preferred and vapor-preferred paths are analyzed in a single channel. A boiling flow pattern map of R-1234ze(E) in the PHE is developed in terms of liquid and vapor superficial momentums, and the criteria for the transitions of the flow regimes are proposed to provide a reference for predicting flow characteristics during phase changes. Based on the measured surface temperatures, the partial dry-out is observed at medium to high vapor qualities in the center of the vapor-preferred path owing to the lack of the liquid phase. In addition, the relationships between the IF, partial dry-out, and heat transfer coefficients are comprehensively analyzed with physical interpretations.
KW - Dry-out
KW - Flow pattern
KW - Flow visualization
KW - Low gwp
KW - Plate heat exchanger
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U2 - 10.1016/j.ijheatmasstransfer.2020.120308
DO - 10.1016/j.ijheatmasstransfer.2020.120308
M3 - Article
AN - SCOPUS:85089549367
SN - 0017-9310
VL - 161
JO - International Journal of Heat and Mass Transfer
JF - International Journal of Heat and Mass Transfer
M1 - 120308
ER -