• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.6
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• pp.541-548
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• 2001

The objective of this study is to analyze the possibilities and considerations for the application of the radiant floor cooling system by analyzing the problems of a conventional cooling system through field tests and thermal performance simulations of the radiant floor cooling in an apartment building. The results are as follows. (1) Problems of he conventional cooling system with PAC()packaged air conditioner)'s include draft, local discomfort, and excessive electrical peak demand. (2) According to the measurement during the cooling and intermediate seasons, the floor surface temperatures which are experienced at the time of cooling with PAC\`s and during intermediate season are similar to the temperatures for radiant floor cooling. (3) The radiant floor cooling system is applicable to apartment buildings during the cooling season, especially on hot and clear days.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.11a
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• pp.116-121
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• 1994

에너지 자원의 고갈과 환경오염 문제가 심각히 대두되고 있는 현재 액체연료에 비하여 청정 에너지인 가스의 연료화에 대한 연구는 과거 어느때보다도 그 중요성이 높이 인식되고 있다. 이에 본 연구에서 제시하는 연소기는 다공성 물질을 이용하는 연소장치로서 연소 경로를 바꾸어줌으로써 공기를 예열하는 효과를 극대화시킴과 대류열및 복사열을 방출하는 것이 큰 특징이다. 본 연구의 결과에 의하면 당량비의 감소에 따른 화염온도는 이론단열화염온도보다 높게 나타나서 당량비의 감소에 비례하여 더욱 좋은 효과를 얻을수 있었으며, 또한 왕복주기시간의 감소함에 따라 화염온도는 약간씩 증가하는 경향을 보여주었다. 이것들은 초희박 연소의 가능성을 보여준 것으로 저발열량의 연료 의 연소로 인한 에너지 절약 또는 유기화합물 즉, 페놀류나 알데히드류와 같은 공해물질들을 제거하는 연소메카니즘에 기여한 할 것이다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.11
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• pp.2995-3002
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• 1995

The cooling problem of the hot internal pipe flow has been investigated. Simultaneous conduction, convection, and radiation were considered with azimuthally varying convective heat loss at the pipe wall. A complex, nonlinear integro-differential radiative transfer equation was solved by the discrete ordinates method (or called S$_{N}$ method). The energy equation was solved by control volume based finite difference technique. A parametric study was performed by varying the conduction-to-radiation parameter, optical thickness, and scattering albedo. The results have shown that initially the radiatively active medium could be more efficiently cooled down compared with the cases otherwise. But even for the case with dominant radiation, as the medium temperature was lowered, the contribution of conduction became to exceed that of radiation.n.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.194-198
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• 2006

In this study, numerical modeling was performed to analyze air flow including radiation heat transfer inside a small chamber. Characteristics of heat transfer between source plate and target through glass are investigated for various surface temperature of heat source plate with buoyancy effect due to gravity force. Conduction heat transfer through the glass is considered and heat source plate is assumed to be a black body. Target surface temperature is largely affected by the radiation heat transfer. It can also be seen that as the source temperature increases target surface is dominated by radiation rather than convective heat transfer by air.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.216-217
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• 2020

As the fire inside the building grows rapidly, ejected flame from an opening occurs due to flashover. As a result, the number of cases where the flame spreads to the exterior of the building and rapidly expands to the upper floor is increasing. In particular, in the case of the fire in the Daebong Green Apartment, Uijeongbu in 2015, it was a case where the flame spread to adjacent buildings due to the opening eruption flame from the first ignited building, causing great damage to three apartments. Therefore, this study is to introduce an international standard under development that estimates the shape and properties of the ejected flame from an opening and quantitatively evaluates the radiant heat flux received by the exterior wall of the building by assuming the occurrence of the ejected flame from an opening.

• Transactions of the Korean Society of Mechanical Engineers
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• v.7 no.4
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• pp.477-482
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• 1983

섬광법의 응용범위를 증대하기 위하여 시편 저, 후면에서 복사와 대류 열손실이 있고, 전면에 임 의 열원이 가해지는 3층 복합재료의 열확산 방정식을 Green 함수를 도입하여 해석하였다. 본 해 석결과는 고체 재료를 1층 재료로 표면처리를 실시한 얇은 층 또는 코오팅 재료를 2층재료로, 용 기내에 들어있는 액체나 기체를 3층 재료로 하여 저온으로부터 고온에 이르기까지 광범위한 온 도에 걸쳐 열확산 계수를 구하는데 응용될 수 있다.

• 연구논문집
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• s.25
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• pp.31-45
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• 1995

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.21 no.5
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• pp.418-422
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• 1992

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.4
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• pp.26-49
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• 2018

The purpose of this study was to verify the reliability of the solar radiation model and discuss its applicability to the urban area of Seoul for summer heat stress mitigation. We extended the study area closer to the city scale and enhanced the spatial resolution sufficiently to determine pedestrian-level urban radiance. The domain was a $4km^2$ residential area with high-rise building sites. Radiance modelling (SOLWEIG) was performed with LiDAR (Light Detection and Ranging)-based detailed geomorphological land cover shape. The radiance model was evaluated using surface energy balance (SEB) observations. The model showed the highest accuracy on a clear day in summer. When the mean radiation temperature (MRT) was simulated, the highest value was for a low-rise building area and road surface with a low shadow effect. On the other hand, for high-rise buildings and vegetated areas, the effect of shadows was large and showed a relatively low value of mean radiation temperature. The method proposed in this study exhibits high reliability for the management of heat stress in urban areas at pedestrian height. It is applicable for many urban micro-climate management functions related to natural and artificial urban settings; for example, when a new urban infrastructure is planned.

• Fire Science and Engineering
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• v.28 no.4
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• pp.97-103
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• 2014

To ensure adequate protection from the risk of burns, fire fighter's turnout has a composite of more than three components and air gaps between layers of materials. During the flame exposure, radiation and convection heat transfer occurs in the air gap, thus the air gap acts as a thermal resistance with non-linear characteristics. Therefore, in this study, the experiments were performed to identify the effect of various air gap width (0~7 mm) on the thermal protective performance of fire fighter's clothing. The temperatures on each layer and RPP (Radiant Protective Performance, the most effective index representing the thermal protective performance) were measured with various incident radiant heat fluxes. The temperature at the rear surface of the garment decreased and RPP increased with increasing air gap width because the thermal resistance increased. Especially, it could be found that RPP value and air gap width has almost linear relation for the constant incident heat flux conditions. Thus relatively simple RPP predictive equation was suggested for various incident heat flux and air gap conditions.