• 한국생산제조학회지
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• 제22권3_1spc호
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• pp.551-557
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• 2013

The heat transfer performance and pressure drop characteristics of brazed-plate heat exchangers with 20 and 30 plates were experimentally measured and analyzed in this study. The mass flow rates of the heat exchangers with 20 and 30 plates were fixed at 0.6 and 0.9 kg/s for the low temperature side, respectively. The mass flow rate for the high temperature side was controlled from 0.2 kg/s to 1.2 kg/s. The inlet temperatures for the high and low temperature sides were $10^{\circ}C$ and $7^{\circ}C$, respectively. The heat transfer characteristics were not influenced by the number of plates. The pressure drop at the heat exchanger with 30 plates was slightly higher than that with 20 plates. The values calculated from the correlations based on gasket plate heat exchangers were compared with the experimental results. It was found that the predicted Nusselt numbers for the gasket plate heat exchangers were about 5% to 20% lower than the measured Nusselt numbers for the brazed plate heat exchangers. However, a pressure drop comparison showed that the calculated pressure drops at the gasket plate heat exchangers were less than half of the measured pressure drops at the brazed plate heat exchangers.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.477-482
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• 2001

An experimental study on the performance evaluation of a brazed plate heat-exchanger with 10RT of normal cooling capacity has been carried out. In the present study, a brazed type plate heat exchanger was tested at a chevron angle $25^{\circ}$ with refrigerant R-22. Mass flux was ranged from $23\;to\;58kg/m^{2}s$ in condensation, and from $22\;to\;53kg/m^{2}s$ in evaporation. The heat transfer coefficient and pressure drop increased with the mass flux increases. The water side pressure drop increased with the cooling water flow rate and chilled water flow rate increases, while mass flux has little affect. It is also shown that the system performance can be improved by enlarging condensation heat transfer area.

• 설비공학논문집
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• 제14권1호
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• pp.83-90
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• 2002

An experimental study on the performance evaluation of a brazed plate heat exchanger with 10USRT of normal cooling capacity has been carried out. In the present study, a brazed plate heat exchanger was tested at a chevron angle $25^{\circ}$with refrigerant R-22. Refrigerant mass flux was ranged from 23 to 58 kg/$m^2$s in condensation, and from 22 to 53 kg/$m^2$s in evaporation. The heat transfer coefficients and pressure drops are increased as the mass flux increases. The water side pressure drop is increased as the cooling water flow rate and chilled water flow rate increase, while mass flux has little effect. It is also shown that the system performance can be improved by enlarging condensation heat transfer area.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.304-310
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• 2000

The experimental study has been conducted on heat transfer characteristics of the plate heat exchangers(PHE) by several researchers. However most of all were focused on a gasket-type plate heat exchanger. Therefore further studies are need for a brazed-type. In the present study, a brazed type plate heat exchanger was tested at a chevron angle of $70^{\circ},\;55^{\circ}$ and $45^{\circ}$ with R-22 and R-410A. Condensation temperatures were $24.5^{\circ}C$, and mass flux was ranged from 35 to $60kg/m^2s$. The inlet and exit conditions are in a superheated vapor and subcooled liquid, respectively. The heat transfer coefficient increased with the chevron angle. The heat transfer coefficient of R-22 was lamer than that of R-410A for all chevron angles.

• 설비공학논문집
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• 제13권3호
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• pp.174-183
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• 2001

Experimental study has been carried out on the characteristics of pressure drop and heat transfer of brazed plate heat exchangers using R-404A. Data are presented for the following range of variables: the mass flux ($20~80kg/m^2s$), chevron angle($20^{circ}C,\;35^{circ}C,\;45^{circ}C$) and inlet pressure of he refrigerant (1.4 and 1.6 MPa). for both subcooled and tow-phase flow, as chevron angle increases, pressure drop and heat transfer coefficient decrease. Condensation hat transfer coefficient and pressure drop was compared with the previously proposed correlations. Among them, Traviss correlation agreed with experimental results within -35~82% for heat transfer coefficient and -73~93% for pressure drop.

• 한국결정성장학회지
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• 제30권6호
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• pp.237-243
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• 2020

본 연구에서는 STS-316 플레이트와 구리(Cu) 브레이징으로 구성된 접합 판형 열교환기(BPHE, Brazed Plate Heat Exchanger)의 내식성과 열효율 성능 향상을 위해 실란계 코팅을 적용하고자 하였다. 코팅 재료에 따른 부식 및 접촉각을 평가하여 선정된 코팅재료를 열교환기에 적용하였으나, 전열 성능 평가 결과 코팅하지 않은 열교환기에 비해 열효율이 떨어지는 결과가 나타났다. 이는 접합 판형 열교환기 내부의 유로에 코팅제의 고착화 및 표면의 잔여 코팅제가 열저항으로 작용하여 열전달을 방해는 것으로 분석되었다. 이는 내부에 미세한 유로가 존재하는 판형 열교환기의 구조적인 특성에 기인한 것으로, 판형 열교환기 제작 공정에서 사전에 유로 표면에 코팅 후 제작하는 것이 전열성능을 향상 시킬 수 있을 것으로 판단된다.

• 설비공학논문집
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• 제26권11호
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• pp.522-528
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• 2014

This experimental study measured and analyzed the heat transfer and pressure drop performance of brazed plate heat exchangers. Heat exchangers with different plate numbers of 10, 20, 30, and 40 were used for measurement, and their plate pattern was identical. The experiment was performed with distilled water, by changing the hot-side flow rate, with the cold-side flow rate fixed. The experimental results were compared with the calculated values by correlations based on gasketed plate heat exchangers, and showed that the heat transfer performance and pressure drop of brazed plated heat exchangers were higher than those of gasketed plate heat exchangers. From the variation of the friction factor, it could be inferred that in the flow channels of brazed plate heat exchangers, turbulent flow occurred at Reynolds numbers higher than 500. A new correlation to predict the Nusselt number was developed, and its absolute average deviation was 2.62%, compared with the values from the experimental data.

• 한국수소및신에너지학회논문집
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• 제14권1호
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• pp.53-60
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• 2003

Performance evaluation on thermal transport of a plate heat exchanger has been carried out. The $\varepsilon$-Ntu method is employed to evaluate the performance of a brazed type of plate heat exchanger. This problem is of particular interest in the design of a plate heat exchanger. The characteristics of heat transfer as well as pressure drop are studied in the wide range of Reynolds numbers in the cold side while that of hot side is fixed at 620. f-factor correlation in a plate heat exchanger is obtained from the pressure drop data. It is also found that the effectiveness of the plate heat exchanger is increased as the Ntu is increased.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2273-2278
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• 2007

Brazed Plate Heat Exchanger (BPHE) is a type of compact plate heat exchanger with parallel corrugated plates which are brazed together in series. Each plate hascorrugation called herringbone pattern. Inside a BPHE, hot fluid and cold fluid alternate its flow direction to establish counter current flow configuration. Two-phase flow heat transfer and pressure drop of R-22 in BPHE were experimentally measured in this study. In the present experiments, single-phase region and two-phase region coexist in a BPHE. Therefore, the inside of a BPHE have to be divided into single phase region and two phase region and analyzed accordingly. The results from the single phase flow analysis are then extended to the two phase flow analysis to correlate the condensation and evaporation heat transfer and pressure drop for the refrigerant R-22 in the BPHEs. Previous models for two- phase friction factor have been compared with the present experimental results.

• 신재생에너지
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• 제18권2호
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• pp.73-81
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• 2022

This study was aimed at designing a condenser, as a component of the organic Rankine cycle system for ships. The condenser was manufactured through press molding to achieve a bent shape to enhance the heat transfer performance, considering the shape of the heat transfer plate used in a brazing plate heat exchanger. The heat transfer plate was made of copper-nickel alloy. The required heat transfer rate for the condenser was 110 kW, and the maximum number of layers was set as 25, considering the characteristics of high-temperature brazing. Computational fluid dynamics techniques were used to perform the thermal fluid analysis, based on the ANSYS CFX (v.18.1) commercial program. The heat transfer rate of the condenser was 4.96 kW for one layer (width and length of 0.224 and 0.7 m, respectively) of the heat transfer exchanger. The fin efficiency pertaining to the heat transfer plate was approximately 20%. The heat flow analysis for one layer of the heat exchanger plate indicated that the condenser with 25 layers of heat transfer plates could achieve a heat transfer rate of 110 kW.