• KIEAE Journal
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• 제12권4호
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• pp.89-95
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• 2012

At present, many countries are trying to reduce green gas emissions to mitigate the effects of these gases on climate change. Year after year, there have been efforts to cut energy use for heating and cooling. Heating and cooling systems, common in all forms of housing, are increasing due to the constant supply of new housing resulting from improvements in economic growth and the quality of life. Thus, studies related to the design of cooling and heating systems to improve energy efficiency are expanding. Among the new designs, radiant floor cooling and heating systems which use capillary tubes are becoming viable means of reducing energy use. Radiant floor cooling and heating systems which use capillary tubes are creative and sustainable systems in which cool and hot water is circulated into capillary tube which has small diameter. In this study, the cooling and heating performance of this type of capillary tube system is investigated in an experimental study and a simulation using TRNSYS. The results of the experimental study show that under a peak load, a capillary tube radiant floor cooling system using geothermal energy can achieve desired indoor temperature without an additional heat source. The set room air temperature is maintained while the floor surface temperature, PMV and PPD remain within the comfort range. Also, this system is more economic than a packaged air conditioner system due to its higher COP. The results of the simulation show that the capillary tube radiant floor heating system maintains set temperature more stable than a PB pipe radiant floor heating system due to its lower supply temperature of hot water. In terms of energy consumption, the capillary tube radiant floor heating system is more efficient than the PB pipe radiant floor heating system.

• 설비공학논문집
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• 제6권4호
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• pp.337-343
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• 1994

Numerical analysis was applied to a simplified two-dimensional Ondol heating model which consists of heating space on the top of it along with radiant and convective heating floor panel, flue channel in the midway and rectangular underground soil region at the bottom. These three components constitute a system thermally coupled at the top and bottom interfaces of the flue channel. Investigated in the present paper are effects with variations of the Reynolds numbers of 100, 200, and 300, Grashof numbers of $0.1{\times}10^6$ and $0.3{\times}10^6$ and aspect ratios of 15 and 20 on the heat transfer and fluid flow characteristics of two-dimensional Ondol heating model by computer simulation.

• Journal of the Korean Wood Science and Technology
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• 제39권3호
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• pp.269-280
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• 2011

오늘날 지구온난화는 전 세계적으로 가장 주요한 문제 중 하나로 부각되고 있다. 이러한 지구온난화는 급속한 에너지 사용량의 증가에 의한 이산화탄소 발생의 증가가 가장 큰 원인이 된다. 그러므로 이에 대비하기 위해서 는 모든 영역에서 에너지 절약에 대한 노력이 필요하다. 세계의 총에너지 사용량 중 건설 활동과 건물운영에서 사용되는 에너지량이 차지하는 비율이 절반이 넘는 것으로 조사되었다. 따라서 건물에너지 발생량을 줄이는 것은 전체 에너지량을 절감시키는 중요한 역할을 한다. 이에 건물에너지 소비에 대한 관심의 증대와 함께 건물의 에너지 소비와 $CO_2$ 발생량을 줄이기 위해 친환경 건축물 등급 및 인증이 요구되고 있다. 건물에너지를 줄일 수 있는 여러 가지 요인 중에서 재료의 열전도율은 패시브적인 방법으로 건물에너지를 직접적으로 줄일 수 있는 가장 기본적인 요소라 할 수 있다. 특히 전통적으로 바닥 복사난방시스템을 사용하는 우리나라의 주거건물에서 바닥마감재의 열전도율은 난방에너지 효율을 결정하는 중요한 요인이다. 본 논문에서는 주거건물의 난방에너지 절감을 위해 건축 재료의 열전도율 측정방법을 조사하고 난방 효율 평가를 위한 축소모형을 제안하였다.

• 에너지공학
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• 제24권1호
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• pp.24-31
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• 2015

바닥복사난방 공간에서 생활특성과 착의량에 따른 열쾌적 범위를 제시하고 각 조건별 에너지사용량 및 비용을 산출하여 비교하는 것을 목적으로 하였다. 좌식생활이 입식생활보다 낮은 온도에서 중립적 온도를 나타냈는데 바닥표면과 인체사이의 국부적인 열전달이 전신온열감에 영향을 주었기 때문으로 판단된다. 착의량이 높을수록 낮은 온도에서 중립점 온도를 나타냈는데 착의량을 증가시키면 인체에서 방출되는 열손실이 감소하여 낮은 실내온도에서 동일한 열쾌적을 느낄 수 있기 때문으로 판단된다. 좌식생활방식이 입식생활방식보다 평균 6.0%의 에너지 사용량이 절감되는 것으로 나타나 좌식생활이 경제적인 생활방식으로 분석되었다. 착의량 1.2 Clo 상태가 착의량 1.0 Clo 상태보다 평균 13.5%, 착의량 0.8 Clo상태보다 평균 18.0%의 에너지 사용량이 절감되는 것으로 나타나 동절기에 착의량을 증가시키는 생활습관의 변화만으로도 에너지 절감 효과가 큰 것으로 분석되었다.

• KIEAE Journal
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• 제15권1호
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• pp.97-102
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• 2015

Recently many buildings are airtight, deterioration takes the high stage. As this room ventilation is increasingly difficult, the importance of indoor air was emphasized. And Got a few provisions on the indoor ventilation, the building is used for other purposes also requires a lot of careful research. In this study, consisting of floor heating ventilation in the room and wants to know the impact on the human body react with the carbon dioxide concentration in the indoor air were investigated PMV. We have get the data through the experimental study like this. It can be inferred correlations of ventilation and temperature according to human comfort that you should consider when using the work of residential buildings in accordance with the changing social conditions and social. It is also determined that in the future through additional experiments related data can be established basic experimental data.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.1073-1074
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• 2008

This paper presents outdoor reset control based on fuzzy algorithm for radiant floor heating system. We construct fuzzy system under indoor temperature and outdoor temperature. Simulation is based on TRNSYS with MATLAB. MATLAB is calculating and decide heat source using fuzzy system. Energy efficiency of Fuzzy algorithm is analyzed in term of indoor by TRNSYS System.

• 한국주거학회논문집
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• 제7권2호
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• pp.121-129
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• 1996

This study was to estimate how about various effects on the body thermal sensation as air velocity. clo. mean radiant temperature and resultant temperature are varied. The indoor thermal environment elements are measured under the five different of air velocity. Using the above considerations. the following results are obtained. ▶ The states, the air velocity under 0.5 m/s and 0.63 to 0.9 clo. were shown that the comfort zone of mean radiant temperature by 21.2~24.7C, the neutral point by 22.8C, the resultant temperature by 20.7-24.4C and the neutral point by 22.6C. ▶ On equal condition, the draft was occurred at a given air-velocity under 0.5m.s. It was also appeared the floor panel heating system affecting the body thermal sensation by the subject’s below-chest parts and the local discomfort by sensations on the feet and the knees.

• 설비공학논문집
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• 제27권9호
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• pp.455-462
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• 2015

Residential buildings account for a significant portion of the total building-energy usage in Korea, and a variety of research studies on the domestic boiler have therefore been carried out; however, most of these studies examined the boiler itself, whereby the part-load ratio characteristics and the corresponding gas-energy consumption patterns were not analyzed. In this study, the part-load ratio and operating characteristics of a domestic gas boiler were analyzed within a residential building equipped with a radiant floor-heating system; in addition, the energy consumption between condensing and conventional boilers was comparatively analyzed. Our results show that significant portions of the total operating hours, heating load, and energy consumption are in the part-load ratio range of 0 through 40%, whereby the energy consumption was significantly affected by the boiler efficiency under low part-load conditions. These results indicate that the part-load operation of a boiler is an important factor in residential buildings; furthermore, replacing a conventional boiler with a condensing boiler can reduce annual gas-energy usage by more than 20%.