• 설비공학논문집
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• 제17권9호
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• pp.839-848
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• 2005

Plastic plate heat exchangers have many advantages over the conventional heat exchangers such as aluminum plate heat exchangers, rotary wheel heat exchangers and heat pipe heat exchangers which have been used for ventilation heat recovery in the air-conditioning systems. In the present study, pressure drop and heat transfer characteristics of plastic plate heat exchangers are investigated for various design parameters and operating conditions which affect the performance of the plastic plate heat exchangers. In flat plate type heat exchanger, material thickness and channel height of heat exchanger are considered, and corrugate size and heat transfer area are considered in case of corrugate type heat exchanger. Pressure drop and effectiveness of the corrugate type heat exchanger increase as the corrugate size decreases.

• 설비공학논문집
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• 제24권8호
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• pp.636-645
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• 2012

The performance of various type plate exchangers with different chevron angle, dimple size and arrangement was analysed by using Ansys v13.0. Heat transfer performance, pressure drop and flow patten of plate heat exchanger were investigated according to mass flow ratio investigated and compared. As a result, the $60^{\circ}$-chevron type plate heat exchanger showed the highest heat transfer performance but pressure drop was relatively high. The efficiency of $45^{\circ}$-chevron type plate heat exchanger showed the best performance in considering of heat transfer performance and pressure drop simultaneously. Among dimple type plate heat exchangers, the highest heat transfer performance was shown in a dim_zigzag type plate heat exchanger but pressure drop was very high. Besides, the dim_upsize plate heat exchanger showed very low pressure drop.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.25-30
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• 2000

Plate and shell heat exchanger(P&SHE) has been applied to the refrigeration and air conditioning systems as evaporators or condensers fur their high efficiency and compactness. The purpose of this study is to analyze the characteristics of pressure drop in plate and shell heat exchanger. An experiment for single phase (low pressure drop in plate and shell heat exchanger was performed. Also numerical work was conducted using the FLUENT code for $ {\kappa}-{\varepsilon}$ model. The dependence of friction factor on geometrical Parameters was numerically investigated. The study examines the internal flow and the pressure distribution in the channel of plate and shell heat exchanger. The results of CFD analysis compared with experimental data, and the difference of frictor factor in plate side and shell side are 10% and 12%, respectively. Therefore, the CFD analysis model is effectively predict the performance of plate and shell heat exchanger.

• 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.

• 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.

• Journal of Advanced Marine Engineering and Technology
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• 제28권6호
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• pp.1026-1036
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• 2004

In this study, single-phase heat transfer experiments were conducted with Oblong Shell and Plate heat exchanger using water. An experimental water loop has been developed to measure the single-phase heat transfer coefficient and pressure drop in a vertical Oblong Shell and Plate heat exchanger. Downflow of hot water in one channel receives heat from the cold water upflow of water in the other channel. Similar to the case of a plate heat exchanger, even at a very low Reynolds number, the flow in the Oblong Shell and Plate heat exchanger remains turbulent. The present data show that the heat transfer coefficient and pressure drop increase with the Reynolds number. Based on the present data, empirical correlations of the heat transfer coefficient and pressure drop in terms of Nusselt number and friction factor were proposed. Also, performance prediction analyses for Oblong Shell and Plate heat exchanger were executed and compared with experiments. $\varepsilon$-NTU method was used in this prediction program. Independent variables are flow rates and inlet temperatures. Compared with experimental data, the accuracy of the program is within the error bounds of $\pm$5% in the heat transfer rate.

• 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.

• International Journal of Air-Conditioning and Refrigeration
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• 제17권2호
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• pp.52-60
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• 2009

The purpose of this research is to develop high efficiency plastic plate heat exchangers which can be substituted for conventional aluminum plate heat exchangers. Four simulation models of plastic plate heat exchangers are designed and simulated: that is, flat plate type, turbulent promoter type, corrugate type and dimple type heat exchanger. The flat plate type is designed as the reference model in order to evaluate how much thermal performance increases. The turbulent promoter type is fabricated with cylindrical-type vortex generators and rib-type turbulent promoters. The corrugate type is obtained from the conventional stainless steel compact heat exchangers, which are called the herringbone-type compact heat exchangers. The dimple type has a number of dimples on its surface. In this study, the flow and heat transfer characteristics of the plastic plate heat exchanger are investigated using numerical simulation and compared with experimental results. Numerical simulation is carried out using the FLUENT code. The flows are assumed as a three-dimensional, incompressible and turbulent model. The computational analysis and experimental results both show that the friction coefficient and Nu number is highest in the corrugate type. The tendency of numerical simulation results is in good agreement with that of the experimental results.

• 대한기계학회논문집B
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• 제32권9호
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• pp.676-682
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• 2008

Numerical analysis was carried out to examine the heat transfer and pressure drop characteristics of plate heat exchangers for absorption application using Computational Fluid Dynamics(CFD) technique. A commercial CFD software package, FLUENT was used to predict the characteristics of heat transfer, pressure drop and flow distribution within plate heat exchangers. In this paper, a welded plate heat exchanger with the plate of chevron embossing type was numerically analyzed by controlling mass flow rate, solution concentration, and inlet temperatures. The working fluid is $H_2O$/LiBr solution with the LiBr concentration of 50-60% in mass. The numerical simulation shows reasonably good agreement with the experimental results. Also, the numerical results show that plate of the chevron shape gives better results than plate of the elliptical shape from the view points of heat transfer and pressure drop. These results provide a guideline to apply the welded PHE for the solution heat exchanger of absorption systems.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2363-2368
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• 2008

The objectives of this paper are to measure the heat transfer and pressure drop of the plate heat exchangers for absorption system applications. Three types of plate heat exchangers with different chevron angles are tested in the present experiment. Heat transfer and pressure drop performance of plate heat exchangers are measured in various operating conditions, and compared each other. The results show that the heat transfer rate of high theta ($120^{\circ}$) and mixed theta plate heat exchanger increases about 118% and 98% at the solution flow rate 350 kg/h compared to that of low theta ($60^{\circ}$), respectively. The effectiveness of high theta was evaluated about $0.70{\sim}0.83$ in this experimental range.