• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.7 no.2
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• pp.64-72
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• 1978

The determination of solar collector area requires a thermal simulation to evaluate the performance of a solar house. This study comprises a simulation of system performance including a solar house, flat-plate collectors, a water type storage tank and an auxiliary heater. Developing the steady state performance equations of each equipment, and using the actual monthly average weather data for several recent years, this study evaluates the hourly performance of a solar house model. As a result, it is shown that the desirable collector area in Seoul is 1.4-1.6 times larger than the heating area in the case of non-selective surface, 0.8-1.0 times in the case of selective surface.

• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.214-219
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• 2008

This study is describes thermal performance of solar cooling and hot water for demonstration system with ETSC(Evacuated tubular solar collector) installed at Seo-gu culture center of Kwanju. Control condition for solar cooling and hot water system is changed by connection of auxiliary heater. Demonstration system was connected to central air conditioning system. Demonstration system was operated by two types. First type(A) was operated to cooling and hot water supply in that order. Second type(B) was operated to hot water supply and cooling in that order. As a result. it was indicated that the total solar energy consumption of (A) was 799 MJ and the solar energy consumption rate for the cooling and hot water supply was 70% and 30% respectively. Total solar energy consumption of (b) was 898 MJ and the solar energy consumption rate for the cooling and hot water supply was 31% and 69% respectively.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.217-222
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• 2011

This study examined the cooling performance of a solar heating and cooling system for an office building using the dynamic simulation program (TRNSYS). This solar heating and cooling system incorporates evacuated tube solar collectors of $204m^2$, storage tank of $8m^3$, 116.2kW auxiliary heater, single-effect $LiBr/H_2O$ absorption chiller of 20RT nominal cooling capacity. It was found that for the representing day showed peak cooling load the annual average collection efficiency of the collector was 32.9% and coefficient of performance of single-effect $LiBr/H_2O$ absorption chiller was 0.68. And the results shows for the cooling season the solar fraction of the solar heating and cooling system was 32.2% and maximal and minimal solar fraction was 63.4% for May 17.9% for July respectively.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.597-601
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• 2006

The advantages of solar energy are that it is renewable, infinite supplied and environmentally safe energy source. However, solar energy related products have the problems such as the limitation for installation, problems in maintenance and insufficient reliability which have been the barrier to consumers to satisfy the purchase need for solar heat related products. In this regard, in order to support the solar energy related companies the necessity for various technical information required for the commercialization of new products such as various performance test necessary for the certification of solar energy system, standardization for facilities and products, performance evaluation method and the measurement of performance is suggested. The purpose of this paper is to design the monitoring system for positive tests of system linked household hot water system using solar heat out of various solar energy systems, to establish an analysis and monitoring system for performance maintenance and operation technique, and to configure the centralized detection network by utilizing remote monitoring system. This research also aims at conducting monitoring for operation and performance evaluation in relation to database establishment and analytical evaluation and at describing the method of enhancing the reliability of solar energy system through the development of performance evaluation program.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.360-363
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• 2012

A solar air heating has low efficiency compared with the solar water heating because the heat capacity of the air is small. The heat received by solar collector plate is not fully transferred to the air and then a part of them became the losses to the environment through conduction and convection process. This research is focusing on a design of better combined multi-purposed system suggested by us and aims to secure the more efficient solar energy utilization by combining the hot water and air heating system. The result in this paper has shown that the proposed design has better thermal performance than that of the common design. Furthermore, it was found that the performance of the combined air - water heating system increases the efficiency from 30% to 35%-40%.

• Journal of the Korean Wood Science and Technology
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• v.52 no.1
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• pp.47-57
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• 2024

Solar energy is one of the most promising options for renewable energy and biomass is one of them. One of the main biomass sources, sugarcane bagasse, is produced annually in more than hundreds of nations worldwide exceeding 4.25 billion tons. To dry a 900-mm deep fixed bed of wet sugarcane bagasse, a solar air heater with a collector area of 2 m² was installed. Between October 10^th to 19^th in Gwangju, South Korea, a 9-day drying period, the solar collector received a total of 496,145 kJ of solar radiation. During this time, 54.5 kg of water was extracted from 133 kg of wet sugarcane bagasse (average green moisture content of 47.6%_w.b.). The estimated net heat from the evaporation of water removed during the dying period accounted for approximately 27% of the total solar radiation on the solar collector.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.1
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• pp.336-345
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• 1996

A theoretical and experimental study was conducted in order to design highly efficient solar air heaters using porous material. Radiative characteristics of glass windows and porous absorbing media were correlated through spectral transmittances measured by the UV-Visible and the FT-IR spectrometers. Using those characteristics the efficiencies of collectors were numerically calculated with the use of the two-flux radiation model. Based on the theoretical results, an experimental solar collector was designed and constructed. Experimental results under various conditions show that the daily efficiencies are over 60% in general and agree well with the theoretically calculated ones.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.15 no.3
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• pp.292-298
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• 1986

The new f-chart capable of estimating long-term thermal performance of solar space and water heating systems was developed. The system comprise a flat plate solar collector, heat exchanger, storage tank filled with water, auxiliary fuel fired heater, and a house structure. The information obtained from many simulations of solar heating systems has been used to develop this f-chart. Actual hourly meteorological data collected in Seoul, Daejeon, Kwangju and Daegu, Korea from 1979 to 1983 have been utilized in these simulations. The new f-equation is as follows: $$f=1.034Y_{-}0.0968X_{-}0.2235Y^2+0.0043X^2+0.0144Y^3$$. The system performance estimates obtained from the developed f-chart are in close agreement with the results of experiment.

• Journal of the Korean Solar Energy Society
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• v.35 no.4
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• pp.43-55
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• 2015

This paper presents the thermal hydraulic performance of a three dimensional rib-roughened solar air heater (SAH) duct with the one principal wall subjected to uniform heat flux. The SAH duct has aspect ratio of 12.0 and the Reynolds number ranges from 2000 to 12000. The roughness has relative rib height of 0.045, ratio of dimple depth to print diameter of 0.5 and rib pitch ratio of 8.0. The flow attack angle is varied from $35^{\circ}$ to $70^{\circ}$. Various turbulent flow models are used for the heat transfer and fluid flow analysis and their results are compared with the experimental results for smooth surfaces. The computational fluid dynamics (CFD) results based on the renormalization k-epsilon model are in better outcomes compared with the experimental data. This model is used to calculate heat transfer and fluid flow in SAH duct with the compound roughness of V-shaped ribs and dimples. The overall thermal performance based on equal pumping power is found to be the highest (2.18) for flow attack angle of $55^{\circ}$. The thermo-hydraulic performance for V-pattern shaped ribs combined with dimple ribs is higher than that for dimple rib shape and V-pattern rib shape air duct.

• Journal of the Korean Solar Energy Society
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• v.27 no.3
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• pp.55-61
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• 2007

This paper has been conducted to estimate cooling capacity of the dehumidification tower using hot water from a solar water heating system as a energy source of regeneration process when the dehumidification and drying system is applied to room cooling. A solar water heating system was operated and indoor temperature distributions were simulated according to weather conditions when the concerned solution was used to dehumidify room air in the dehumidification tower. Through this simulation researches we found th following results ; It was found that air velocity through supply and return diffusers should be controlled because it can cause uncomfort in dwelling area. It was found that in the sunny morning temperatures of dwelling area 1 and 2 are higher than those of dwelling area 3 and 4. In this research all the calculation results of heating and cooling system supported by solar water heater have confirmed that its cooling capacity could not reach PMV 0, thermal comfort.