• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.1
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• pp.166-175
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• 1996

In recent years, air-conditioning units designed with higher efficiency and more compactness are required due to emphasis on energy efficiency in home electrical appliances. This trend in the air-conditioning industries has accelerated the development of improved heat exchanger with a better performance in heat transfer aspects. In this study, experiments were performed to investigate the shape and configuration of fins affecting on the performance of the conventional fin-and-tube type heat exchanger equipped in a commercial air conditioners. The geometry similtude method was employed to measure the heat transfer coefficient and pressure drop. Experimental results show that this method is very useful to analyze the heat transfer characteristics of the fin-and-tube type heat exchanger. It is also found that the slit fin has better performance than the conventional fin type in the air conditioners. The present results indicate that heat transfer from the fin si influenced by the parameters such as the forming area of the slit fin, the type of interrupted surfaces like a louver or slit, slit patterns and slit raised direction, and it also affects the overall heat exchanger performance.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.1107-1112
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• 2006

The purpose of this study is a heat transfer coefficient test of evaporator tube in shell and tube heat exchanger by shapes, using R-404A. The experimental apparatus is designed to simulate the real heat transfer rate in one shell and tube heat exchanger. The test section is formed four type tubes that are Inner ridged tube, Corrugated tube, Turbo-C tube, Inner fin tube and shell type is formed by electrical heater. All tests were performed at a fixed refrigerant evaporator temperature at $1.5^{\circ}C,\;-3^{\circ}C$ and with mass fluxes of 29, 25 kg/hr. Heat transfer rate is calculated a enthalpy difference in test section. In experiment, heat transfer coefficient measured one by one and electrical heaters are supplemented by evaporator.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1348-1354
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• 2009

The purpose of the present study is to investigate the flow resistance and the heat transfer characteristics of V type circular fin-tube heat exchanger. Four kinds of V type fin having the same fin area and the different span wise angle tested numerically. Test data for the heat transfer, pressure drop and fin temperature were shown and discussed. The pressure drop and heat transfer increased for decreasing the span wise angle up to 58% and 25% respectively.

• Journal of the Korean Society of Industry Convergence
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• v.11 no.4
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• pp.157-163
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• 2008

The present study investigated the pressure drop and the total frost mass of the louvered fin type heat exchanger, which is widely used at the air-conditioning system. The pressure drop due to the frosting phenomenon and the total frost mass were investigated by changing the wet bulb temperature condition of the inlet air. Hence the brain of 55wt% was used as a cooling solution instead of a common refrigerant. The temperature difference between the brine and the tube outside wall at the outlet of heat exchanger was $10^{\circ}C$, at maximum, higher than that at the inlet of heat exchanger. As the wet bulb temperatures were increased, the pressure drop was linearly increased due to the increment of frost mass. And the increment of heat exchange rate was smaller than that of inlet air enthalpy due to the increment of frost mass. The pressure drop of air side was rapidly increased due to the progress of frosting phenomena. The run time that the pressure drop occurred rapidly was decreased by the growth of frost.

• International Journal of Air-Conditioning and Refrigeration
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• v.9 no.2
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• pp.28-35
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• 2001

This study deals with the thermal characteristics of finned-tube heat exchanger having two rows used in the air-conditioning application. Pressure drop and heat transfer coefficient were measured by using the three times models of plain fin and compared with the theory. Also the temperature distribution and heat conduction in the fin was measured by using the liquid crystal method. The surface temperature of rear row was nearly constant, and heat conduction in the fin was stronger near the front row than the rear row.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.7 no.1
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• pp.161-170
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• 1995

This study is concerned with the numerical analysis of performance on fin-tube heat exchanger under frosting condition. In this work, tube-by-tube method using LMED is employed. The present results are compared with O'Neal's experimental and numerical results. A standard evaporator model with 2rows-2columns is selected to investigate the effects of the various parameters such as fin pitch, air flow velocity, and humidity. The results show that frost thickness and the amount of frost per unit area decrease as fin-pitch becomes narrower. In the meantime, frost thickness and accumulation rate increase with higher inlet air humidity. It is shown that heat transfer rate increases during 30minutes and then it decreases. Heat transfer rate and the amount of frost increase with air velocity, however frost thickness does not increase over a certain velocity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.3
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• pp.470-475
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• 2009

In the present study, the heat transfer characteristics of the fin-tube and PF heat exchangers and the performances of the air-conditioner are experimentally investigated. Also, Cooling Seasonal Performance Factor(CSPF) of the air-conditioner is evaluated. For the heat exchanger experiment, the heat transfer and pressure drop are obtained. For the air-conditioner experiment, the cooling capacity, input power and COP are obtained. The air-enthalpy calorimeter and the constant temperature water bath are used. As the inlet air velocity increases, the heat transfer rate and pressure drop of the heat exchanger increased. PF heat exchanger has smaller refrigerant weight and larger capacity and COP than the fin-tube heat exchanger. The performance of PF-2 heat exchanger with the squarer fin is more excellent than that of PF-1 heat exchanger with the triangler fin. Also, CSPF of the fm -tube and PF heat exchanger is evaluated.

• Journal of Electrochemical Science and Technology
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• v.14 no.4
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• pp.349-360
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• 2023

This study investigated the tri-metallic galvanic coupling of different metals in the tubes, fillers, and fins of a heat exchanger. The goal was to prevent corrosion of the tubes using the fin as a sacrificial anode while ensuring that the filler metal has a more noble potential than the fin, to avoid detachment. The metals were arranged in descending order of corrosion potential, with the noblest potential assigned to the tube, followed by the filler metal and the fin. To address a reduction in protection current of the fin, the filler metal was modified by adding Zn to decrease its corrosion potential. However, increasing the Zn content of filler metal also increases its corrosion current. The study examined three different filler metals, considering their corrosion potential, and kinetics. The results suggest that a filler metal with 1.5 wt.% Zn addition is optimal for providing cathodic protection to the tube while reducing the reaction rate of the sacrificial anode.

• Solar Energy
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• v.10 no.1
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• pp.14-21
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• 1990

The entropy generation rate in a fin-tube heat exchanger is investigated as a basis for thermodynamic optimization associated with single fin-tube heat exchanger. The entropy generation (irreversibility)analysis is used to find the optimum design factor and investigate total entropy generation, optimum dimensions of fin length, tube inner and outer diameters, and fin spacing on the variation of design factors. The results of this study are as follows: As the outer diameter increases, optimum !in spacing and fin length increase but the entropy generation and optimum inner diameter decrease; As fin thickness increases, the entropy generation of system and optimum fin spacing increase; As fin length increases, entropy generation and optimum outer diameter increase.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2002.05a
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• pp.21-27
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• 2002

Catalytic combustor with heat exchangers are often employed in process technology where a compact design is required [1]. The use of fin and tube heat exchanger offers the enhanced surface area for heat exchange. The recent progress and performance of the fin-tube heat exchanger, especially airside, has been reviewed extensively by Wang[2].(Omitted)