Local Condensation Heat Transfer Characteristics of Refrigerant R1234ze(E) Flow Inside a Plate Heat Exchanger

• Published in: International journal of air-conditioning and refrigeration Vol. 25; no. 1; pp. 1750004 - 11
• Main Authors: Mahmud, Mohammad Sultan, Kariya, Keishi, Miyara, Akio
• Format: Journal Article
• Language: English
• Published: World Scientific Publishing Company 01.03.2017; 대한설비공학회
• Subjects: 기계공학; condensation; Local heat transfer; plate heat exchanger; R1234ze(E)
• ISSN: 2010-1325; 2010-1333
• DOI: 10.1142/S2010132517500043

In the present study, local condensation heat transfer coefficients of the R1234ze(E) inside a vertical plate heat exchanger (PHE) were investigated experimentally. In the experiment, three vertical flow channels are formed in the test section where refrigerant flows downward in the middle channel and cooling water flows upward in other two channels. The test section consists of eight plates: two of them form a channel of chevron type PHE for refrigerant flow channel, other two flat plates are set for heat transfer measurements, and another consist on cooling water flow channel. Down flow of the condensing refrigerant R1234ze(E) in the center channel releases heat to other channels of cooling water. In order to measure local heat transfer characteristics, a total of 60 thermocouples were set at middle of flow direction and also in the right and left sides of plates in test section. Experiments were conducted for mass fluxes ranging from 10 kg/m2s to 50 kg/m2s. The measurement results show that local heat transfer coefficients decrease with increase of wetness with different values in horizontal direction. Further, characteristics of local heat flux and wall temperature distribution as a function of distance from inlet to outlet of refrigerant channel were explored in detail.