• 설비공학논문집
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• 제25권9호
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• pp.516-521
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• 2013

In the present study, the performances of a fin-tube evaporator and three PF evaporators for a heat pump dryer were experimentally investigated. Among the tested evaporators, the PF3 type evaporator showed the highest values of heat transfer capacity and dehumidification performance, while the fin-tube evaporator had the lowest values. PF3 showed better performance compared to PF1 and PF2, due to the large pin pitch, which leads to more draining for dehumidified water. Also, the $45^{\circ}$ inclined PF evaporator presented better performance than that of the $90^{\circ}$ inclined PF evaporator, owing to its easier draining characteristics. The effect of air velocity was revealed to be quite large. When the air velocity increased by 20%, the heat transfer capacity and dehumidification performance increased 43%/11%, 48%/13% and 54%/23% for PF1, PF2 and PF3, respectively.

• 설비공학논문집
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• 제16권8호
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• pp.741-747
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• 2004

The purpose of this study was to develop a cooler/heater using a thermoelectric module combined with a parallel flow type oscillating heat pipe with R-142b as a work ing fluid. The experiment was performed for 16 thermoelectric modules (6 A/15 V, size: 40${\times}$40${\times}$4 mm), varying design parameters of the heat pipe (inclination angle, working fluid charging ratio, etc) . Experimental results indicate that the optimum charging ratio and the inclination angle of the parallel flow type oscillating heat pipe were 30% by volume and 30%, respectively. The maximum cooler/heater capacity were 479W (COP : 0.47) and 630W (COP : 0.9), respectively.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1267-1271
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• 2009

In the present study, performance characteristics on environment change of A/C applied fin-tube and PF heat exchangers were experimentally investigated. Capacity and COP changing an outlet air velocity, an indoor/outdoor temperature and a relative humidity were obtained. Air－enthalpy calorimeter was used. As the air velocity, indoor temperature and relative humidity increase, capacity and COP increase. PF A/C has smaller refrigerant weight than the fin-tube A/C. The performance of PF-2 A/C with the squarer fin was more excellent than that of PF-1 A/C with the triangler fin.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.340-345
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• 2008

A computer program, which simulates the parall flow evaporator was developed. The program was having used to simulate the sample $650\;mm{\times}190\;mm$ frontal area, 25 mm flow depth and 3.0 mm fin pitch. It was shown that the cooling capacity of 3kW could be available from the sample. The present model, however, does not consider refrigerant mal-distribution in each pass, which is known to reduce the cooling capacity of the parallel flow heat exchanger.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.314-320
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• 2000

In this study, the wet surface heat transfer coefficients and friction factors of PF heat exchangers are presented. Two sample with different fin pitch(1.25mm, 1.5mm) were tested. Tests were conducted in a open loop wind tunnel. The wet surface heat transfer coefficient was reduced following the procedure given in ARI 410-81. Results showed that the heat transfer coefficients of the heat exchanger with 1.5mm fin pitch were approximately the same as those with 1.25mm fin pitch, except at low reynolds number(Re<100), where the heat transfer coefficients of 1.5mm fin pitch were slighly higher than those with 1.25mm fin pitch. The friction factors of the 1.25mm fin pitch, however was 120 % to 160 % higher than those of the 1.5mm fin pitch. The wet surface heat transfer coefficients were lower than those of the dry surface. The wet surface friction factors, however, were higher than those of the dry surface.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.483-488
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• 2006

In this study, newly-developed slim electronic panel cooler with aluminum PF condenser and evaporator was tested and the results are compared with imported panel cooler with fin-tube heat exchangers. The PF heat exchangers significantly (approximately 45%) reduced the refrigerant charge. The air-side pressure drop was also reduced, which resulted in the reduction of the sound level of the panel cooler. The effect of the condenser size was also investigated.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.519-524
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• 2008

In the present study, the air-side heat transfer and pressure drop characteristics of the fin-tube and PF heat exchangers have been experimentally investigated under the cooling standard condition. Fin type of PF heat exchanger is a triangler and squarer form. The experimental data of the slit fin-tube and two kinds of PF heat exchangers are measured using the air-enthalpy calorimeter and the constant temperature water bath. As the inlet air velocity increases, the heat transfer rate and pressure drop of the heat exchanger increased. The heat transfer rate and pressure drop of PF-2 heat exchanger of the squarer fin is larger than that of PF-1 heat exchanger of the triangler fin. As the inlet air temperature increases, the heat transfer rate decreases and the pressure drop is nearly uniform.

• 한국산학기술학회논문지
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• 제10권3호
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• pp.470-475
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• 2009

본 연구에서는 핀-관 열교환기와 PF 열교환기의 열전달 특성과 이를 적용한 공조기의 성능을 비교 조사하였다. 또한 공조기의 냉방기간 에너지효율(CSPF)을 평가하였다. 열교환기 실험을 위해 3종류의 열교환기에 대한 열전달 및 압력강하를 그리고 공조기 성능평가를 위해 냉방표준, 냉방저온에서 냉방능력, 소비전력, COP를 산출하였다. 실험은 칼로리미터와 항온수조를 사용하여 수행되었다. 유입공기 속도가 증가함에 따라 열교환기의 열전달율과 압력강하는 증가하였다. PF 열교환기 적용 시스템의 적정 냉매량은 핀-관공조기보다 약 $15{\sim}20%$ 감소하였으나, 냉방능력은 증가, 소비전력은 감소하여 COP는 향상되었다. 사각형 핀을 가진 PF 열교환기가 삼각형 핀보다 냉방능력과 COP가 더 우수하였다. 실환경 온도조건을 반영하기 위해 PF 열교환기와 핀-관 열교환기 적용 시스템의 CSPF가 계산되었다.

• 한국산학기술학회논문지
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• 제10권8호
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• pp.1789-1794
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• 2009

본 연구에서는 핀-관 열교환기와 평행류(PF) 열교환기를 실외 열교환기로 적용한 공조기의 실내외 온도/습도와 같은 환경변화에 대한 냉방성능을 비교 조사하고자 하였다. KS C 9306의 냉방표준 온도조건을 기준으로 핀-관, 2종류의 PF 열교환기를 적용한 공조기 성능변화를 이해하기 위하여 냉방능력과 COP를 획득하였다. 실험을 위해 공기엔탈피 방식의 칼로리미터를 사용하였다. PF 열교환기는 핀-관 열교환기보다 우수한 열전달 능력을 보였다. 그리고 사각형 핀을 적용한 PF형 공조기의 성능이 삼각형 핀의 경우보다 우수하였다. 실내 토출공기의 유속, 실내온도 그리고 실내상대습도가 높아질수록 냉방능력과 COP는 증가를, 실외온도가 높아질수록 냉방능력과 COP는 감소를, 그러나 실외 상대습도 증가에 따른 성능변화는 미미하였다.

• 한국산학기술학회논문지
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• 제14권4호
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• pp.1576-1581
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• 2013

본 연구에서는 히트펌프 건조기용에 적용될 PF 열교환기에 대하여 연구되었다. PF 열교환기의 설치 경사각($0^{\circ}$, $30^{\circ}$, $60^{\circ}$)에 따른 3종 PF 열교환기의 능력과 제습량을 측정하였다. 실험은 건구온도 $60^{\circ}C$, 상대습도 70%, 풍속 0.5m/s에서 진행되었다. 실험결과 경사각이 증가할수록 열교환기의 성능이 우수하였으며, PF3가 능력과 제습량에서 가장 우수하였다. 그러나 경사각이 $60^{\circ}$에서는 능력과 제습량이 크게 감소하였다. 실험값을 예측하기 위해 PF 열교환기의 능력과 제습량을 예측할 수 있는 계산프로그램을 개발하였다. PF 열교환기 3종에 대한 실험값과 계산값은 능력의 경우에 최대 2% 이내를 제습량의 경우에 최대 3% 이내에서 만족한 결과를 보여주었다.