• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.11 no.1
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• pp.1-6
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• 2015

This study presents analysis of the experimental data meeting conditions of several applications in real time. The results of this experimental study are as follows: Respectively in cooling and heating performance, a refrigerant charge tank can take automatic control of variation of the refrigerant quantity by controling pressure and temperature of system and outlet water temperature. The COP shows 3.5 in cooling operation and 3.2 in heating operation. The refrigerant quantity increases 0.69 kJ/h. When the outdoor temperature decreases $1^{\circ}C$, Therefore if the temperature become lower from $25^{\circ}C$ to $-16^{\circ}C$, the refrigerant quantity increases about 9.5%. Compared to the normal state experiment results, the COP in automatic control of the refrigerant quantity rises roughly 10%.

• Journal of Korean Association for Spatial Structures
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• v.8 no.1
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• pp.77-88
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• 2008

This research aims to divide the large enclosures according to summer and winter seasons, and to measure changes in the indoor thermal conditions. Also, with regard to air conditioning and exterior environments, it aims to identify the characteristics of indoor thermal environments such as indoor vertical and horizontal temperature distribution in large enclosures, temperature distribution in the audience's seating, indoor surface temperature distribution, wind speed distribution in the audience's seating, and indoor thermal comfort.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.333-337
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• 2011

Central control air-conditioning systems are being replaced with individually controlled air-conditioning system in the university. The amount of growth of electricity consumption is due to the increasing demand of electric heat pump. In winter and summer, the energy consumption showed a tendency to increase. On the other hand, showed less energy in spring and autumn. Increase the amount of electricity than the degree of decline in gas consumption was higher. Can be considered as transitional phenomena. Because electric heat pump, gas driven heat pump and the absorption chiller-heater are used at the same time in some of the buildings.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.8
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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.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.204-209
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• 2002

본 실험은 주택용, 일반용, 교육용, 산업용, 농사용, 심야전력 등 국내의 종별요금체계에 따라 인공광을 이용한 접목묘 활착촉진장치에서 소비된 전기에너지와 전력요금을 비교하고자 수행되었다. 그 결과 전력요금은 일반용>교육용>산업용>심야전력>농사용의 순서로 나타났으며 접목묘 1주를 활착시키는 데 필요한 전기요금은 농사용의 경우 9.24원이었으며, 일반용 전력요금과 비교할 때 봄과 가을, 겨울, 여름철의 1주당 생산단가는 각각 2.3배, 2.4배, 3.4배로 나타났다. 또한 본 실험에서 소비된 전력은 컴프레서, 가열기, 조명, 가습기, 송풍기의 순서로 각각 28%, 57%, 11%, 3%, 1%로 나타났다. 활착촉진장치에서 소비된 전력 가운데 공조 시스템, 즉 냉·난방이 차지하는 비중이 전체의 85%로서 매우 높게 나타난 바, 공조 시스템에 대한 전력소모량의 절감 방안이 우선적으로 강구되어야 할 것으로 판단된다.

• 월간 기계설비
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• s.236
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• pp.48-51
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• 2010

국토해양부(장관 정종환)는 최근 연세대 친환경건축연구센터와 서울시 강동구가 협의('09.8)를 통해 친환경 공동주택 가이드라인을 마련함에 따라 강동구부터 '저에너지 친환경 공동주택 가이드라인' 시행에 들어 간다고 밝혔다. 가이드라인의 주요내용은 공동주택 재건축시 냉 난방 에너지 총 소비량의 40% 이상을 절감하고, 관리동 등 공용시설의 제로에너지화, 지역특성에 맞게 생태면적률 40%이상 확보, 단지내 인공생물 서식공간 조성의 의무화 등이다. 강동구는 앞으로 지어지는 재건축정비사업의 공동주택 모두에 가이드라인 내용을 반영하여 친환경 공동 주택으로 건설을 추진할 계획이며, 특히 고덕지구($1,239,407m^2$, 18,540가구) 및 둔촌지구($626,235m^2$, 9,090가구)부터 적용하여 친환경공동주택단지를 조성할 전망이다.

• Journal of Bio-Environment Control
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• v.6 no.3
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• pp.216-224
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• 1997

In the recent 10 years the protected cultivation area in Korea has been increased rapidly, and now it is very important issue to develop the heating and cooling system using the renewable energy, because the greenhouse heating and cooling cost is increased with the fossil fuel price rises. Actually the development of the cooling system is more difficult than that of the heating system, since the cooling load of greenhouse in the summer season is 2―3 times larger than the heating load in the winter season. In this study low temperature phase change materials (LTPCM) for the cold storage system were selected and developed. The theoretical and experimental analysis of thermal characteristics of LTPCM makes it possible to control the phase change temperature and stabilize the thermo-physical properties. LTPCM developed in this study has good advantages to be used as the cold storage not only for the house and working space in factory but also for the cold storage of agricultural and live-stock products.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.207-212
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• 2013

In this study, distributed the ship's Centralized Air Conditioning System the way an individual to replace the air conditioning system by using Air-cooled air conditioner. Research results, Individually separated air conditioning system complement the heat source control and thermal efficiency problems and improves the efficiency of the device was confirmed. In addition, under the same conditions refrigeration capacity and coefficient of performance of the device, an average of about 3 %, 23 ~ 26 %, higher, Chilled Water Plants Compressor power consumption is about 12 % lower. Also while heating under the same conditions, power consumption is about 33.5 % lower. Therefore Individually Separated Air Conditioning System greatly contributed to the improved performance of the device and living spaces for comfortable temperature and humidity control as well as heating source could be obtained.

• Journal of Energy Engineering
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• v.22 no.2
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• pp.83-89
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• 2013

Energy consumption is closely related to our lives. As Korea has four seasons, heating and cooling system is considered as essential facilities for the residential buildings. Accordingly, the government has continuously strengthened the design criteria to improve energy for new and existing building to save energy. The most important factor in the energy efficiency analysis for apartment is the heat transmission coefficient, and the value is significantly different as the heating energy amount is greatly different according to the window area ratio versus facade area ratio. Therefore, it is time to conduct continuous set-up for goal to enhance efficiency and restriction on window area ratio versus facade area ratio.

• KIEAE Journal
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• v.9 no.4
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• pp.11-16
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• 2009

To act and respond to the climate changes and to bring about power-saving in buildings, the changes in the atmospheric data in Korea are recorded and assessed. For the two regions representative of Korea, the data obtained from HadCM3 and actual data are compared and analyzed so as to concretely evaluate and confirm the changes taking place in the cooling and heating degree days in Korea. For the past 40 years, from 1996 to 2005, the number of heating degree days was on the decline and in the two representative regions, between 1980's and 1990's, the number of decrease in the heating degree days had been quite large. The number of cooling degree days showed a trend of increase since the 1970's and just as in the case of heating degree days, the extent of increase was quite large between the 1980's and the 1990's. The results of comparison of the number of heating and cooling degree days, one obtained from the "Korea Meteorological Administration" and another from the HadCM3 data (E127.5,N37.5,E127.5,N35), which is one of the ways of predicting the climate, showed similar trends in the number of heating degree days in the Yeosu area. However, in the case of the number of heating degree days in Seoul and the number of cooling degree days both in Seoul and Yeosu, the differences in the number ranged from a minimum of 300 days to a maximum of 1500 days. This could be attributed to the grid points used in the HadCM3, the differences in the values of latitudes and longitudes of these two locations considered in this study, topographical differences, heat island effect caused by population density etc. and while using the HadCM3, these variables factors must be taken into consideration.