• Journal of Biosystems Engineering
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• v.15 no.2
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• pp.123-133
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• 1990

Thermal performance of a solar heating plastic greenhouse designed for a hydroponic system was studied. The system was constructed with the air-water heat exchanger and thermal storage tank that were combined with hydroponic water beds. Experiments were carried out to investigate the daily average heat stored and released in thermal storage tank, average solar energy collection efficiency, average coefficient of performance, average oil reduction factor of thermal storage system, and the heat transfer coefficient during the nighttime in plastic greenhouse. The results obtained in the present study are summarized as follows. 1. Daily average heat stored in thermal storage tank and released from the thermal storage tank was 1,259 and $797KJ/m^2$ day, respectively. 2. The average solar energy collection efficiency of thermal storage tank was 0.125 during the experiment period. And the average coefficient of performance of thermal storage system in plastic greenhouse was 3.6. 3. The average oil reduction factor of thermal storage system and the heat transfer coefficient during the nighttime in plastic greenhouse were found to be 0.52 and $4.3W/m^2\;hr\;^{\circ}C$, respectively.

• Journal of the Korean Solar Energy Society
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• v.25 no.2
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• pp.53-62
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• 2005

In this study, the thermal performance of multi-story double-skin facade(DSF) with variation of cavity height is evaluated to offer useful data in determining cavity height of multi-story DSF. For this, thermal criteria for multi-story DSF is adopted and a DSF model for evaluation of the thermal performance is established. Through the evaluation of CFD simulation, the recommended height of multi-story DSF is 5 stories or less to improve the thermal performance during the intermediate season.

• Solar Energy
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• v.8 no.1
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• pp.22-32
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• 1988

It is known that the energy consumption and indoor thermal comfort in residential buildings are affected by the thermal performance of building envelopes. The thermal performance of building envelopes varies with their design methods. In this study, the thermal performance changes by the insulating construction types of exterior walls were analyzed, 1) by varing the thickness of the insulation 2) by varing the location of the insulation 3) by varing the location of the plane airspace The analyzed results are presented and the thermal performance evaluating factors were compared and discussed.

• KIEAE Journal
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• v.17 no.4
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• pp.59-65
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• 2017

Purpose: Thermal performance and air tightness of window are improved for the building energy efficiency. As the deteriorated houses are increased, the improve measures with low cost and easy installation are developed in the energy performance of window. Attached glazing and windbreak can be easily applied to the window with low cost. In this paper, the effect of the attached glazing and windbreak on the thermal performance and air tightness of window is analyzed as the measure to improve performance of window. Method: Thermal transmittance of glazing is evaluated through WINDOW simulation according to thickness of attached glazing and air cavity. Based on the simulation results, thermal transmittance, air tightness and condensation resistance performance of four cases are tested according to Korea standards. One type of PVC sliding double window is chosen as the specimen. For the analysis on low performance of window, the outside of window is excluded in the PVC sliding double window. Result: This study shows that thermal performance of glazing can be increased by the application of attached glazing. Furthermore, lower thermal performance of glazing can obtain the higher effect of attached glazing. The application of attached glazing and windbreak can effect on increasing thermal performance and air tightness of window.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.11a
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• pp.269-272
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• 2009

The temperature of PV modules that integrated into building facades or roof increases that could reduce the electrical efficiency of the PV system. In order to incresae PV system's efficiency it is very important to remove the heat from the PV modules. For this purpose, hot air can be extracted from the space between PV modules and building envelope, and used for heating in buildings. The solar collector utilizing this thermal effect is called photovoltaic-thermal(PVT) solar collector. This paper compares the experimental performance of building-integrated PVT collectors that applied on building roof and facade. There are two different case: a roof-integrated PVT type and a facade-integrated PVT type. The experimental results show that the collected thermal energy of the roof-integrated type was 24% higher, compared to that of the facade-integrated.

• Journal of the Korean Solar Energy Society
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• v.33 no.3
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• pp.51-57
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• 2013

Metal curtain wall systems are widely used in high-rise commercial and residential buildings. While aluminum is the most frequent used frame material, steel framing is also reemerging as a high-performance material in glazed curtain walls due to less thermal conductivity and design flexibility. The purpose of this study is to evaluate thermal performance of a steel frame curtain wall system by comparing with a aluminum frame curtain wall system. The thermal transmittance was measured according to KS 2278, and condensation resistance was calculated by the test results according to KS F 2295. The steel framing test specimen showed lower thermal transmittance and temperature descending factor compared to the aluminum framing test specimen.

• KIEAE Journal
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• v.14 no.3
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• pp.79-86
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• 2014

Studies have shown that the thermal performance of buildings changes depending on the year of construction completion. It leads to increased energy consumption of buildings and significant financial burden on users. Thus, this study has calculated the thermal insulation performance of 86 apartments quantitatively, using temperature difference ratio and sensible heat flux. Also, energy consumption characteristics depending on the year of construction completion and thermal insulation performance were analyzed by comparatively analyzing the results of insulation performance evaluation and heating costs. The analysis results are as follows. As for thermal insulation performance, it was around 70% lower in the apartments completed before 1985, compared to apartments completed after 2010. As for heating costs, the apartments with the highest heating cost incurred 1.5 higher heating cost than the apartment with the lowest heating cost. In terms of the insulation performance evaluation, the difference was 2.5-fold.

• Journal of the Korean Solar Energy Society
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• v.35 no.1
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• pp.1-8
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• 2015

In the present study, the effects of the heat spreader thickness and the heat sink size on the thermal performance of a cooling device for a concentrating photovoltaic (CPV) module were numerically investigated. Numerical simulation was conducted by using the simulation tool ICEPAK, commercial software based on the finite volume method. Numerical results were validated by comparing the existing experimental data. The thermal performance of a cooling device, which consisted of a heat spreader and a natural convective heat sink, was evaluated with varying the heat spreader thickness and the heat sink size. The geometric configuration of the natural convective heat sink, such as the fin height, the fin spacing, and the fin thickness, was optimized by using the existing correlation. The numerical results showed that the thermal performance of the cooling device increased as the heat spreader thickness or the heat sink size increased. Also, it was found that the spreading thermal resistance plays an important role in the thermal performance of the cooling device which has the localized heat source.

• Journal of the Korean Wood Science and Technology
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• v.44 no.2
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• pp.184-190
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• 2016

Recently, wood is attracting attention as green building interior decoration material. When wood is used as building interior decoration material, excellent dimensional stability and thermal performance is required. In this study, superheated steam treatment process and thermal compression process were applied to flat sawn Pinus koraiensis wood panel in order to improve dimensional stability and thermal performance. According to results of this study, superheated steam treatment process and thermal compression process improve thermal performance and dimensional stability of wood, especially in tangential direction. The spring back in radial direction reduces the effect of thermal compression on dimensional stability of wood in radial direction.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.3
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• pp.150-155
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• 2013

Usually, a window tends to have a lower thermal performance, than that of an ordinary wall. This study analyzes the enhancement of thermal performance of a window, when a Thermal Insulation Shutter is installed. The analyses were conducted at the laboratory, and with a full-scale mockup house, and the U-factor and heating load were examined. The laboratory results show that the U-factor increased by approximately 28%, when a Thermal Insulation Shutter was installed. The temperature difference was about $5^{\circ}C$, and this shows that the Thermal Insulation Shutter enhances the thermal performance of the window, when installed. The mockup house was used to calculate the heating load; the heating load was reduced by more than 41%, and shows that the installation of a Thermal Insulation Shutter is an effective way to reduce heating energy consumption.