• 설비공학논문집
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• 제14권2호
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• pp.116-126
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• 2002

A three dimensional numerical analysis of the corrugated louver fin for a vehicle heat exchanger was performed. The heat transfer rate and the air pressure drop of the corrugated louver fins for a slim heater were compared with experimental results at the same operating conditions. As for the slim heater fin, we found an optimum fin pitch at certain operating conditions. As the fin pitch increased, the air pressure drop decreased. The vertical or flat top fin was superior to the common declined fin in the aspect of heat transfer performance. As the louver length increased, both the heat transfer rate and the air pressure drop increased.

• 설비공학논문집
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• 제21권2호
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• pp.87-93
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• 2009

Slim telecommunication cabinet cooler, equipped with parallel flow heat exchangers and operating with R-22, is developed. The performance is compared with imported one, equipped with fin-tube heat exchangers and operating with R-134a. Test results show that the newly-developed cooler increases the cooling capacity by 6% and EER by 33%. The refrigerant charge for the developed cooler is 500g compared with 1250g for the imported one. The adoption of parallel flow heat exchanger appears to have reduced the refrigerant charge. In addition, it is shown that the reduced air flow rates through parallel heat exchangers as compared with those through fin-tube heat exchangers are beneficial to the reduction of the equipment noise.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.15-19
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• 2006

유출지하수나 지표수를 열원으로 하는 지열히트펌프의 Pond Loop형 열교환기를 개발하기 위하여 미국에서 상용화된 Slim-Jim 열교환기와 본 연구에서 자체설계, 제작한 Pond-loop type의 열교환기를 유동이 없는 유출수조 내에서 수조온도가 변화함에 따라 일정한 열교환기 입구온도를 유지하면서 열전달량의 변화를 측정하였다. 그 결과 유출수를 Heat Source로 사용하는 경우 Slim-Jim에서는 $8,000{\sim}11,000 kcal/hr$의 열량이 전달되었고, 자체 제작한 열교환기에서는 $11,000{\sim}16,000kcal/hr$의 열량이 전달되었다. 유출수를 Heat Sink로 사용할 경우 Slim-Jim에서는 $2,500{\sim}7,000 kcal/h$의 열량이 전달되었고, 자체제작한 열교환기의 경우, $6,800{\sim}14,00 kcal/hr$의 열량이 전달되었다. 측정된 열전달량을 바탕으로 총괄열전달계수를 구한 결과 Slim-Jim 열교환기의 경우 $210{\sim}340 kcal/hr\;m^2{\circ}C$, 자체개발한 열교환기의 경우 $350{\sim}590 kcal/hr\;m^2{\circ}C$로 나타나 자체 개발한 열교환기의 열전달 성능이 비교적 우수함을 입증하였다.

• 대한기계학회논문집B
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• 제41권9호
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• pp.587-595
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• 2017

최근 들어 공조기가 슬림화 되고 따라서 열교환기의 깊이를 줄일 필요가 있다. 본 연구에서는 슬림형 알루미늄 열교환기에 적절한 루버 핀 형상을 도출하였다. 또한 도출된 루버 핀이 적용된 알루미늄 열교환기 시료를 제작하고 성능 시험을 수행하였다. 비교를 위하여 기존 열교환기에 대해서도 실험을 수행하였다. 도출된 형상의 핀 깊이($F_d$)는 10.0 mm, 루버 핏치($L_p$)는 0.9 mm, 루버 각(${\theta}$)은 $35^{\circ}$이다. 기존 시료에 비하여 신규 슬림 시료의 j 인자는 36%, f 인자는 2.3% 크게 나타났다. 따라서 열교환기 체적은 슬림 시료에서 26% 줄어들게 된다. 또한 동일 소비 동력에서의 전열량을 의미하는 $j/f^{1/3}$은 슬림 시료에서 55% 크다. 실험 데이터를 기존 상관식의 예측치와 비교하였다.

• 설비공학논문집
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• 제17권2호
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• pp.95-100
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• 2005

Numerical simulations and experiments were conducted to analyze the design parameters for a slim room air-conditioner. These design parameters included a fan shape, a front panel, a scroll shape, a bell mouth, a distance between a fan and a heat exchanger, etc. Each design parameter was analyzed numerically and/or experimentally in terms of the flow rate and the sound pressure level, which should be the most influential factors for developing the slim room air-conditioner. The fan with a uniform height showed a better performance than that with a linearly varying height. It is recommended to use a front grill rather than a front panel according to sound pressure levels since the front panel itself is a huge resistance to the inlet flow. A redesigned scroll shape by changing the rotational direction of a fan also contributed a lot to lowering the sound pressure level. There existed a distance between a fan and a heat exchanger, where flow rates increased effectively.

• 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.

• 한국소음진동공학회논문집
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• 제26권4호
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• pp.383-390
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• 2016

In this paper, experiment and dynamics simulations were carried out to identify and reduce the out-of-plane vibration that occurs in a centrifugal fan of an air conditioner installed to a wall. In a wall-installed air conditioner, large space between a case and heat exchanger is often required for the fan to avoid the collision with the case and exchanger. This large space hinders the slim design of the air conditioner even if air conditioner market demands a slim air conditioner. In the present study, in order to determine the cause of the vibration in the centrifugal fan, the out-of-plane vibration and the physical properties were investigated, and the dynamic characteristics of the centrifugal fan were obtained by experiments. Based on these experiments, a dynamic simulation model was established to determine the cause of the out-of-plane vibration of the centrifugal fan. It was found that the main factor of out-of-plane vibration in the centrifugal fan is the axial misalignment between the centrifugal fan and the motor shaft.