• Journal of the KSME
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• v.33 no.11
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• pp.936-941
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• 1993

최근 소비전력 구제 및 $CO_{2}$ 발생량 구제 등으로 인하여 에너지 절약형 제품에 대한 요 구가 점증하고있어 핵심부품인 열교환기의 효율 향상은 숙명적인 과제라 할 수 있다. 에어컨에 사용되고 있는 응축기와 증발기(condenser/evaporator)는 대부분이 핀-튜브(fin-tube)형의 직교 류형 열교환기 (crossflow heat exchanger)이다. 이와 같은 열교환기의 성능에 영향을 미치는 인자들은 크게 핀과 튜브로 구성되는 기하학적인 인자와 공기부와 냉매부로 나뉘어지는 물리적인 인자로 나눌 수 있다. 이 글에서는 핀-튜브형 열교환기의 설계시 고려하여야 할 기하학적 인자와 물리적 인자에 대하여 기술하고자 한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.2
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• pp.222-229
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• 2009

This study presents comparison of heat transfer and air side friction characteristics in a condenser condition of air conditioner between Louver fin-tube heat exchangers and aluminum parallel heat exchangers. All experiments are performed using an air-enthalpy type calorimeter, which is designed based on the method described in ASHRAE standards. The air velocities crossing the heat exchanger tubes are varied from 0.7 to 1.6 m/s with 0.3 m/s interval, maintaining air dry temperature and relative humidity at $20^{\circ}C$ and 60% respectively. Water temperature and flow rate inside the tube are $70^{\circ}C$ and 10 LPM, respectively. Experimental results show that the heat transfer performances of aluminum heat exchangers are 17-163% higher than those of Louver fin-tube heat exchangers based on the data per unit volume, mass, and heat transfer area, whereas air side pressure drops of aluminum heat exchangers are 19-81% lower.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.4
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• pp.100-105
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• 2004

Fin-tube type(Fin-type) heat exchanger has been tested in order to replace the heat exchanger of parallel flow type(P.F -type) which is now widly used in automobile air conditioning system The following conclusions are drawn by the comparison of the characteristics of the heat exchangers. Evaporator and condenser capacities and COP(Coefficience of performance) were varied as with the compressor speed, outdoor air temperature and air flow rate changed, which much influenced on the characteristics of the air conditioning system Evaporator and condenser capacities were increased with increasing compressor speed and outdoor air temperature. Evaporator and condenser pressures of Fin-type were decreased by 7% and 5% respectively compared with those of P.F-type. The COP of Fin-type was decreased with increasing outdoor air temperature and compressor speed. The COP of P.F-type was decreased by 14% compared with that of Fin-type.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1003-1010
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• 2013

In this study, a simulation program was developed, which predicts the performance of cold-air forced circulation type air cooled showcase. The showcase has an excellent display effect in addition to preserving the grocery. In the program, the compressor was analyzed using performance data supplied by the manufacturer and the capillary tube pressure drop was analyzed using a homogeneous model. The evaporator and condenser were analyzed by dividing the heat exchangers into small elements, where energy balance and appropriate heat transfer correlations were used. A showcase model with two 3/4 HP compressors, capillary tubes of 1.6 mm inner diameter, a fin-and-tube evaporator and condenser was tested, and the results are compared with the predicted values. It is shown that both evaporation and condensation temperatures are adequately predicted by the program.