• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.104-104
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• 2003

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.144-144
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• 2004

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.7
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• pp.462-469
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• 2008

A regenerative evaporative cooler has been fabricated and tested for the evaluation of cooling performance. The regenerative evaporative cooler is a kind of indirect evaporative cooler comprised of multiple pairs of dry and wet channels. The air flowing through the dry channels is cooled without any change in the humidity and at the outlet of the dry channel a part of air is redirected to the wet channel where the evaporative cooling takes place. The regenerative evaporative cooler fabricated in this study consists of the multiple pairs of finned channels in counterflow arrangement. The fins and heat transfer plates were made of aluminum and brazed for good thermal connection. Thin porous layer coating was applied to the internal surface of the wet channel to improve surface wettability. The regenerative evaporative cooler was placed in a climate chamber and tested at various operation condition. The cooling performance is found greatly influenced by the evaporation water flow rate. To improve the cooling performance, the evaporation water flow rate needs to be minimized as far as the even distribution of the evaporation water is secured. At the inlet condition of $32^{\circ}C$ and 50%RH, the outlet temperature was measured at $22^{\circ}C$ which is well below the inlet wet-bulb temperature of $23.7^{\circ}C$.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.3
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• pp.982-991
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• 1991

본 연구에서는 냉방기에서 널리 이용되고 있는 평판핀이 연속적으로 부착된 다관식 증발 열교환기에 대하여 (1) 냉매의 열역학적 물성치의 변화 (2) 냉매와 공기 측 열전달 계수의 변화 (3) 냉매측 관 마찰 손실등을 고려한 시뮬레이션 프로그램을 작성하고 그 결과를 실험을 통하여 보정 완성하였다. 계산결과로 부터 공조기기의 설계조건, 공조계통 해석을 위한 기초자료를 제시하였다.

• Journal of Bio-Environment Control
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• v.22 no.1
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• pp.19-25
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• 2013

In this study, the cooling experiment was carried out in $1,650m^2$ area of the seedling greenhouse from June 6, 2011 to september 18, 2011 with the vertical type geothermal heat pump system of 350 kW scale (175 kW ${\times}$ 2 units) installed in the greenhouse, cooling effects were analyzed and we tried to find more effective operation methods of the geothermal heat pump system. In case of one unit heat pump (175 kW) operation, when evaporator inlet water temperature changed from $13.0^{\circ}C$ to $15.5^{\circ}C$, cooling COP of the system was in 1.1~1.8 range and in case of two unit heat pump (350 kW) operation, when evaporator inlet water temperature changed from 13.0 to 15.5, cooling COP of the system was in 2.0~2.7 range. The accumulated cooling heat quantity of June, July, August and September was 14,718.6, 26,765.1, 28,437.2 and 10,065.0 kWh, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.2872-2877
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• 2012

This paper discusses the development of the wearable personal cooling system for reducing thermal stress in hot environment. The personal cooling system is operated with the compact refrigeration system by compressing refrigerant. The compact refrigeration system is applied with the miniaturization and weight reduction for portable and wearable cooling system. The body heat is reduced by heat conduction with evaporator in direct cooling type. The cooling capacity of the wearable personal cooling system is approximately 100W and, the system could maintain the inside temperature of approximately 12-$13^{\circ}C$ lower than the ambient temperature. The weight of the wearable cooling system is about 3kg including vest, case, battery and all parts.

• Journal of Bio-Environment Control
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• v.32 no.1
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• pp.15-22
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• 2023

Roses are one of the most produced flower species in the world, and cut roses are produced in the greenhouses all year round. Recently, due to the increase in the temperature in the greenhouses in summer, the quality of cut roses is seriously deteriorated, such as shortening the stem length. This study was conducted to investigate the effects of the growing seasons on the qualities of cut roses and also to test the effect of cooling at night in high temperature season on the cut flower qualities of roses. Comparing the qualities and yields of cut roses for each season, the major cut flower qualities such as flower stem length, stem diameter and fresh weight were statistically significantly decreased in roses ('Pink Beauty' and 'Pink Shine') produced in summer. The yields didn't show a statistically significant difference in both cultivars. Investigating the cut flower qualities, the flower stem length increased by 15% for 'Pink Beauty', 11% for 'Ararat', and 12% for 'Pink Shine' when treated with cooling at night in warm season than the untreated control. In addition, when treated with cooling at night in warm season, the fresh weight of all three cultivars increased by 20-30% statistically significantly than conventionally cultivated control. It is expected that cooling at night in warm season will be helpful to improve the cut flower quality deterioration in summer.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.786-788
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• 2005

전력 부하관리기기인 축냉시스템은 그동안 건물 냉방 공조용을 중심으로 보급되었다. 기저부하를 증진시키고 주간의 피크부하를 낮추어 주야간의 부하불균형을 해소하는 축냉시스템은 그동안 전력부하율 향상 및 부하평준화에 많이 기여해왔다. 산업용으로의 축냉기기보급의 타당성 및 부하평준화에 관한 연구시행 결과, 그 타당성과 보급확대의 필요성이 확인 되었다. 가스식 냉방기는 피크억제측면에서, 축냉식은 부하이전 측면에서 장점이 매우 크며, 전체 부하관리 측면에서 이들의 균형보급발전 노력이 필요하다. 산업용으로의 축냉기기 보급은 특히 주야간 부하불균형이 심한 하계의 부하평준화효과가 크며, 그 보급시장 및 전력절감 잠재량 규모를 감안할 때 국가적 편익과 추가 발전설비건설억제에 크게 기여할 것으로 예상된다.

• 보일러설비
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• no.8 s.151
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• pp.104-109
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• 2006

보일러회사들의 사업다각화 기세가 놀라울 정도다. 특히 난방사업과 냉방사업을 아우르는 다각화는 유난히 계절을 타는 보일러 회사들에게는 최적의 조합으로 꼽히고 있다. 귀뚜라미보일러와 경동보일러가 그렇다. 이들 회사들은 동절기를 겨냥한 난방 시즌이 끝나도 하절기를 겨냥한 냉방 시즌이 기다리고 있으니 일년 365일을 항상 같은 템포로 유지할 수 있다. 가을철 추수가 끝나면 기나 긴 농한기에 접어 드는 농촌처럼 한 구석이 허전했던 보일러 회사의 대리점들도 이제는 손발에 땀이 나게 뛰기만 하면 된다. 하지만 귀뚜라미와 경동의 사업 내용은 전혀 다르다. 귀뚜라미는 에어컨의 제조원이고 경동은 판매원이다. 귀뚜라미가 센추리 아산공장을 인수하고 지난달에는 범양공조까지 흡수하면서 에어컨 메이커의 메이저를 꿈꾸고 있는 반면 경동은 세계 최대 에어컨 회사인 캐리어와 손잡고 마케팅 컴퍼니의 메이저 자리를 노리고 있다. 진입방식은 다르지만 냉난방 전문 기업으로 변신을 꾀하고 있는 귀뚜라미와 경동보일러의 에어컨 사업을 들여다 본다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.6
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• pp.784-794
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• 1998

The present study has been directed at developing thermal models to investigate the dynamic behavior of a solar cooling system including an absorption chiller, solar collectors, a hot water storage tank, a fan coil unit, and the air-conditioned space. The operation of the system was simulated for 8 hours in two different operation modes. In the mode 1, the system operated without any capacity control.0 the mode 2, an auxiliary boiler supplied heat to the generator if hot water temperature became lower than a certain value. Moreover, the mass flow rate of hot water to the generator was controlled by comparing the instantaneous room air temperature with the design value. The variation of temperature and concentration in the system components and that of heat transfer rates in the system were obtained for both modes of operation. It was found that the room temperature was maintained near the desired value in the mode 2 by supplying auxiliary heat or controlling the mass flow rate of hot water, while the deviation of room temperature was quite great in the mode 2.