http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Hong Hiki (검색결과 199 건)
- 무료
- 기관 내 무료
- 유료
-
-
-
Measurement Methods of Latent Heat for PCM with Low Melting Temperature in Closed Tube
Hong Hiki,Kang Chaedong,Peck Jong Hyeon The Society of Air-Conditioning and Refrigerating 2004 International Journal Of Air-Conditioning and Refr Vol.12 No.4
Cycle test for developed phase change material (PCM) is necessary in order to assess the variation of latent heat, which decreases with time by deterioration. T-history method and measurement using heat-flux meter are appropriate for the cycle test in a tube filled with PCM because they do not need an extraction of sample in measuring heat of fusion. In the present study, these methods were applied to a PCM having a melting point below a room temperature, different to the past studies for PCMs melting above a room temperature. As a result of experiment using pure water as specimen, we can obtained rea-sonable values for heat of fusion.
-
-
-
-
-
홍희기(Hiki Hong),김시환(Sihwan Kim) 대한설비공학회 2010 설비공학 논문집 Vol.22 No.7
In housing units constructed recently in Korea, the length of ondol coil is different in each room, so the flow rate of hot water is adjusted by setting valve opening. If the flow rate is not appropriate for heating load, the room temperature seriously deviates from the set temperature range for comfort. In particular, too small valve opening can induce a noise by cavitation. In order to adjust the valve opening, two methods by zone area and a new method by return temperature rise were modelled and simulated using TRNSYS and EES. As a result, heating energy consumption during one week was the same on three methods, but the room temperature of the new method minimally deviated from the range of set temperature with a low possibility of noise.
-
홍희기(Hiki Hong),최준영(Junyoung Choi),임신영(Shin Young Im) 대한설비공학회 2017 설비공학 논문집 Vol.29 No.10
Most European economies, Japan, and many governments have made it a major policy to expand the green business by disseminating heat pump technology, which has a large CO2 reduction effect. The heat pump of all heat sources has been recognized as renewable energy and the policy to encourage has been implemented. In the recently revised Renewable Energy Law, the hydrothermal source (surface sea water) heat pump was newly included in renewable energy. In addition, the scope of application of heat pumps has expanded in the mandatory installation of renewable energy for new buildings, remodeling buildings, and reconstructed buildings based on this law. However application to heat pumps using all natural energy as heat source has been put off. In this revision, the ratio of renewable energy to the total energy produced by the heat pump was fixed at 73%, which depends on coefficient of performance of heat pump. The ratio of renewable energy is 1-1.8/COPH, and should be calculated including the coefficient of performance of the heat pump. Using a high efficiency heat pump or a high-temperature heat source increases the coefficient of performance and also reduces CO₂ emissions. It is necessary to expand the application of heat pumps as renewable energy equipment and to improve the correct calculation of renewable energy production.
-
홍희기(Hiki Hong),김선국(Sunkuk Kim),유호선(Hoseon Yoo) 대한설비공학회 2009 대한설비공학회 학술발표대회논문집 Vol.2009 No.-
This study was performed to determine the heating energy savings and CO₂ reduction resulting from turning off ondol heating in housing units in Korea. Lowering the room temperature and intermittent heating of a room are effective methods for reducing heating energy consumption. These techniques were proven by modeling simulations in our previous studies. To confirm the simulations, schedule controllers which automatically turned off the ondol heating in the living room and kitchen from 10 pm to 6 am were in stalled at the hot water distributor in five households. The heating gas used in each of the housing units was measured over a period of five years, with and without the schedule controllers. We found that approximately 30% of gas consumption, mainly used for heating, can be saved compared to turning on the appliance during the night.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
