• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.381-386
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• 2008

In this study, the energy characteristic of automatic thermostatic valves according to each heating method in floor radiant heating system were researched by computer simulation. For the analysis of unsteady heat transfer phenomena in household, the method of using electrical equivalent R-C circuit is applied, and radiation heat transfer between panel, ceiling and walls in household is calculated by enclosure analysis method. The parametric study on heating method, valve's control method, outdoor air condition, supply heating water temperature, supply flow rate are performed to compare energy characteristic, respectively.

• 월간 기계설비
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• s.40
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• pp.84-95
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• 1993

지역난방은 한 곳에 집중된 대규모 열원시설에서 경제적으로 생산된 열을 일정한 지역내 아파트, 빌딩, 공공 시설 등에 난방 및 냉방용으로 공급하는 도시 기반시설이다. 또한 지역난방은 개별난방이나 중앙난방의 간헐 난방방식과는 달리 24 시간 연속난방을 하므로써 건강하고 쾌적한 실내온도를 유지시켜 주며, 노후된 보일러 교체비 및 유지 보수가 들지 않고, 난방순환펌프 등 각종 부대시설의 축소로 동력비를 절감할 수 있으며 기존 보일러실을 주민복지 공간으로 활용할 수 있고, 연료탱크와 보조난방기구 등이 필요 없어 재해 발생의 우려가 없다. 본지에서는 한국지역난방공사에서 제공한 자료와 월간 설비기술에 게재된 내용을 요약 정리하여 게재한다.

• 월간 기계설비
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• s.229
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• pp.64-70
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• 2009

본지는 자동제어설비협의회(위원장 최전남) 제공으로 지난 6월호부터 자동제어시리즈를 게재하고 있다. 이번 호에는 중앙난방 제어 방식으로 김영일 서울산업대학교 교수의 '중앙난방에서 시간표와 On/Off 제어 방식의 비교'를 게재한다. 중앙난방 제어 방식에 대해 기존 시간표에 의한 간헐 난방과 제어 방식 중 가장 간단한 on/off 제어를 실내 온도 변화와 에너지 소비량 실험 및 시뮬레이션 기법을 통한 분석한 결과 간단한 제어 방식이라도 적용할 경우 비적용시보다 쾌적성과 에너지 절약 측면에서 유리한 것으로 나타났다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.8
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• pp.682-691
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• 2001

Most of radiant floor heating systems are operated in the intermittent heating mode in Korea. The application possibility of predictive suboptimal control for Koran residential house was investigated by computer simulation and experiment. For this study, TRNSYS program was used and an experimental facility consisting of tow rooms ($3\times4.4\times2.8 m$) identical in construction was built. The facility enabled simultaneous comparison of two different control method. And real multi residential hose was investigated. Results showed that outdoor air temperature prediction control was superior to the conventional control for radiant floor heating system operated in the intermittent heating mode. New control system resulted in good thermal environment and les energy consumption.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.1
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• pp.88-93
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• 2005

In this study, the operational characteristics on heating performance and energy consumption for intermittent hot water heating system in apartment buildings were research by simulation. The effects of apartment inlet hot water temperature and operation time per day on energy consumption and indoor thermal environment are investigated. The strategy of energy saving and thermal environment improvement is suggested in comparison with the existing ones.

• KIEAE Journal
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• v.7 no.5
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• pp.81-86
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• 2007

The research analyzes the arrangement of boiler and hot water header, the method of radiator pipe setting, hot water supply control, hourly heating situation of each room for underfloor radiant heating systems in Korea and suggests an alternative to improve to efficient heating method. One of the best options for install position of hot water distributor is under kitchen sink which is center point of all rooms, according to previous research of the energy saving strategies. When the radiator pipes are arranged to each individual room instead of bedrooms through livingroom and kitchen, it has energy saving effects. For rooms without occupancy according to a time period, hot water supply method should be intermittent heating rather than continuous heating. For this intermittent heating method, individual control of hot water supply is more practical, and it can lead to massive energy savings. The intermittent heating system has time-lag, so it is more effective in energy saving with mild and comfort condition if the spaces are preheated by automatic control equipment prior to required time.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.1
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• pp.76-87
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• 1996

Energy analysis for the hot water heating control system of apartment house complex is accomplished by computer simulation. Mathematical model of a boiler, pipe network and a unit-house is developed. The effects of heating control methods on the heating performance and energy consumption of the system are investigated. The heating control methods considered in this study are a continuous heating control, and on-off heating control and an intermittent heating control methods. For each control method, the effects of an outdoor temperature, indoor temperature sensing position and the capacities of the boilers and circulating pumps on the heating performance and energy consumption are obtained and "the best" control method is recommended.commended.

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.145-145
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• 2004

• Journal of Bio-Environment Control
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• v.21 no.1
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• pp.1-11
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• 2012

The objective of the present study is to provide data needed to find double covering method to be able to improve environment of temperature, humidity and PPF in tomato greenhouse. The distribution charts of temperature, humidity and PPF which were measured in environment control conditions such as thermal insulation, air heating, roof ventilation and air fog cooling in conventional and air inflated double layers greenhouses were drawn and analysed. The thermal insulation effect of the air inflated greenhouse was the same as that of conventional greenhouse because the temperature between insulation curtain and roof covering material was equal in heating season. The ventilation effect of the air inflated greenhouse was superior to the conventional greenhouse. The temperature distribution in the fog cooled greenhouse was uniform and the cooling effect was about $3.5^{\circ}C$. The condensation on the roof covering surface could be controlled by removing the moisture between insulation curtain and roof covering by using humidifier. The PPF of conventional greenhouse was more decreased than the air inflated greenhouse as time went by because the transmittance of conventional greenhouse declined by dust collected on the inside plastic film owing to rolling up and down operation for ventilation.

• Journal of Animal Environmental Science
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• v.6 no.3
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• pp.175-184
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• 2000

A lab-scale MF membrane reactor was installed to investigate the membrane permeability, characteristics of membrane fouling at each conditions, and quality of permeate (liquid livestock manure) in the separation of solid-matters using membrane. Experiment was divided three filtration type such as follows; continuous filtration, gravity filtration, and intermittent filtration. As a result of experiment, flux 1 LMH was maintained for 7days, and trans-membrane pressure(TMP) was increased gradually under 10cmHg, but it was increased immediately after 10cmHg, respectively. However, the flux was increased, the Tmax was decreased exponential more and more. During the pure-flux test, most of the fouling of membrane was reversible. At the gravity filtration, permeate could be obtained as 1.75 LMH for 3.5days without any other electronic pressure. As an investigation of membrane surface, this study could be decided that the reason of fouling at the lower flux (Run 1 and 2) was attached matters in membrane surface, but at the higher flux (Run 4-6) was concentration polarization.