• 설비공학논문집
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• 제20권3호
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• pp.175-180
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• 2008

Flow quantity to supply to a coil in floor heating system is important to achieve comfortable indoor air condition in the winter season. The hot water header is used to distribute the water into the coil. Experimental study has been performed using the water header that have 5 branches consisted of flow control valves and automatic shut-off valves. Each branch line connected it with X-L pipe. Experimental tests accomplished it to investigate the flow distribution characteristics of the hot water header. Experimental results show that the selection of the pump head and differential pressure are very important to save running energy of the system, and high differential pressure needs more friction loss in the case of suitable differential pressure for balancing of the header.

• 한국태양에너지학회 논문집
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• 제31권5호
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• pp.41-46
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• 2011

In the present work, a new freeze protection method has been proposed for a natural circulation system of solar water heater. Though electrothermal wire is popularly used for the purpose, there are freezing troubles by wire cut-off and excessive electric power consumption. In the experimental device, hot water in a storage tank was circulated by a small pump and used to heat the outdoor pipes if the cold water pipe surface temperature falls lower than a set point. As a result, It was observed that there was no hot water waste while the solar water heating system operated without freeze and burst.

• 설비공학논문집
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• 제11권3호
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• pp.339-348
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• 1999

A computer model was developed in order to predict the temperature distribution and the performance of the vertical tube-in-tube ground coil heat exchanger. This model has been validated by experimental results conducted by ORNL. The heat exchanger performance with the variation of the length is calculated and compared. As results, the heat exchanger performance is proportional to the length but the performance per unit length decreases. The minimum performance of 70m - PVC heat exchanger during cyclic operation for a week is obtained 20,054kJ/h for cooling operation and 13,915kJ/h for heating operation. And minimum temperature difference is $4.64^{\circ}C$ for cooling operation and $2.64^{\circ}C$ for heating operation. In each case, it is noted that the temperature difference between the pipe and the far-field occurs within 0.8m from the heat exchanger.

• 한국지열·수열에너지학회논문집
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• 제6권1호
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• pp.23-28
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• 2010

The objective of this study is to develope ground heat exchanger using PHC pile used to building foundation, and it's element technology. So we made PHC piles into ground heat exchanger and evaluate it's performance. First, we studied PHC pile type, heat exchanger pipe, grouting materials, and present apartment house's foundation condition for PHC ground heat exchanger. As a result we designed BIGS(Building Integrated Geothermal System) prototype. Second, we applied BIGS to apartment houses' utility building in Osan built by Daelim. Third, we monitored heating performance of winter season. 1be result of heating performance was so good to apply to heat & cooling system in building.

• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 1998년도 임시총회 및 학술논문발표요지
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• pp.5-10
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• 1998

최근 온실에 온수 보일러를 설치하여 실내를 가온하는 시스템이 많이 도입되고 있다. 이들 장치들은 설정된 실내온도를 맞추기 위한 온도 제어장치가 부가되어 있지만, 대부분 ON-OFF제어 시스템을 구성하고 있기 때문에 온도 진폭의 현상이 발생하여 온도 제어 정밀성이 떨어지고 에너지소비도 많다. 이 문제점을 해결하기 위하여는 보일러 온수저장조와 온설 내 방열관 사이에 삼방변을 설치하고 설정온도, 실내온도 및 외기온을 비교하여 삼방변의 위치를 조절하여야 한다. (중략)

• 한국수소및신에너지학회논문집
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• 제8권1호
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• pp.23-29
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• 1997

The combustion and smoke emission of an indirect injection diesel engine Were investigated running the engine on Hydrogen/diesel fuels. Hydrogen fuel supplied to the intake pipe was varied 0 to 10 percent of DF2' s heating value. The most inportant finding was that the smoke emission is not decreased with increase of hydrogen fuel supplement. Also, the ignition delay is almost negligible over 10 percent hydrogen fuel mixture.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 하계학술발표대회
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• pp.4-4
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• 2005

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 하계학술발표대회
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• pp.127-127
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• 2005

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2003년도 하계학술대회 논문집
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• pp.214-214
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• 2003

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2004년도 하계학술발표 논문집
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• pp.164-164
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• 2004