Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Korean Solar Energy Society
Journal Basic Information
Journal DOI :
The Korean Solar Energy Society
Editor in Chief :
Volume & Issues
Volume 27, Issue 4 - Dec 2007
Volume 27, Issue 3 - Sep 2007
Volume 27, Issue 2 - Jun 2007
Volume 27, Issue 1 - Mar 2007
Selecting the target year
Sensitivity Analysis of Wind Resource Micrositing at the Antarctic King Sejong Station
Kim, Seok-Woo ; Kim, Hyun-Goo ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 1~9
Sensitivity analysis of wind resource micrositing has been performed through the application case at the Antarctic King Sejong station with the most representative micrositing softwares: WAsP, WindSim and Meteodyn WT. The wind data obtained from two met-masts separated 625m were applied as a climatology input condition of micro-scale wind mapping. A tower shading effect on the met-mast installed 20m apart from the warehouse has been assessed by the CFD software Fluent and confirmed a negligible influence on wind speed measurement. Theoretically, micro-scale wind maps generated by the two met-data located within the same wind system and strongly correlated meteor-statistically should be identical if nothing influenced on wind prediction but orography. They, however, show discrepancies due to nonlinear effects induced by surrounding complex terrain. From the comparison of sensitivity analysis, Meteodyn WT employing 1-equation turbulence model showed 68% higher RMSE error of wind speed prediction than that of WindSim using the
turbulence model, while a linear-theoretical model WAsP showed 21% higher error. Consequently, the CFD model WindSim would predict wind field over complex terrain more reliable and less sensitive to climatology input data than other micrositing models. The auto-validation method proposed in this paper and the evaluation result of the micrositing softwares would be anticipated a good reference of wind resource assessments in complex terrain.
Radiant Cooling by the Plate Viewing the Daytime Sky
Byun, Ki-Hong ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 11~17
The purpose of this study is to check whether the plate temperature could be lower than the surrounding air by using the radiant cooling during the day time in summer at Seoul. Without an insolation shield as this experiment was performed, a few cases were found. The temperatures of the black painted plate are lower than those of the aluminium film coated plate if the following condition exist; no or small insolation over the plate, the wind velocity less than around 2 m/s, and clear sky However if there are insolation over the plate, the temperatures of the aluminium coated plate are lower than the black painted plate. Also, as the wind velocity increases, the plate temperature decreases faster. The temperature response of the small system is much faster than the large system.
Heating and Cooling System using the Sewage Source Absorption Refrigeration and Heat Pump Cycle
Lee, Yong-Hwa ; Shin, Hyun-Joon ; Yoon, Hee-Chul ; Park, Hyun-Gun ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 19~26
This paper concerns the study of absorption refrigeration and heat pump cycle to use sewage. Simulation analysis on the double-effect absorption refrigeration cycle with parallel and two-stage heat pump cycle has been performed. The working fluid is Lithium Bromide and water solution. The absorption refrigeration cycle use sewage as a cooling water for the absorber and condenser, and absorption refrigeration cycle does that as a chilled water for the evaporator of the first stage cycle. And the two-stage cycle consists of coupling double-effect with parallel and single effect cycle so that the first stage absorber and condenser produces heating water to evaporate refrigerant in the evaporator of the second stage. The effects of operating variables such as a absorber temperature on the coefficient of performance have been studied for absorption refrigeration and heat pump cycle.
Demonstration study on Desalination System using Solar energy
Kim, Jeong-Bae ; Joo, Hong-Jin ; Yoon, Eung-Sang ; Joo, Moon-Chang ; Kwak, Hee-Youl ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 27~33
In this research, to develop the practical application system of fresh water generation system with plate-type fresh water generator using low pressure evaporation method is the main object, and to do that, this study used the evacuated solar collector with operating range of about
as thermal energy source and solar photovoltaic as electric energy source. To achieve that object, this study set up the demo-plant, then estimated and analyzed the usefulness, the safety, and the reliability through pre-tests during short time ahead of the long-time operation. This study showed that the pumps, which are including sea water supply, ejector, hot water supply, and fresh water pumps, were operated one after another. And, the fresh water yield was closely related with the solar irradiance and lower supply temperature of hot water was revealed more reasonable for the solar energy desalination system. That is due to the insufficient area than the solar collector area being required that was estimated through the performance tests of the fresh water generator.
Experimental Study on Thermal Performance of Palte-type Fresh Water Generator for applying Solar Energy Desalination System
Kim, Jeong-Bae ; Kwak, Hee-Youl ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 35~41
To demonstrate the desalination system, the demo-plant was scheduled to be installed. The system was planned to use solar thermal collector as heat source and PV as electricity source. For the design of the desalination demonstration system, firstly the solar thermal system would be well designed from the result between the supplied heat into the fresh water generator and the fresh water yield. The generator for demonstration system was chosen as the fresh water generator of the single stage and effect with plate-type heat exchanger using low pressure evaporation method. The test facility for the tests to reveal the relationship between the fresh water yield and the supplied heat flow rate was designed and manufactured. The maximum fresh water yield of two fresh water generators applied in this study was designed as 1.5 Ton/day. The parameters relating with the performance of fresh water generator are known as sea water inlet temperature, hot water inlet temperature, and hot water flow rate. Through the experiments, this study firstly showed detail operation characteristics of the generator and designed the solar thermal system for the demonstration system.
The Study on Efficiency Improvement of a Thermal Storage Tank for Solar Combined Heating System
Ryu, Nam-Jin ; Han, Yu-Ry ; Park, Youn-Cheol ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 43~49
This study is conducted to improve the efficiency of a thermal storage tank. The thermal storage tank was designed to store heat energy that obtained from the solar or the others heat sources. However, it has difficulties in storing heat with nonuniform temperature through the entire tank with respect to the vertical direction, This study is focused on the thermal stratification to improve thermal comfort for the resident in house. To enhance temperature stratification of the tank, a distributor was designed and installed in the middle of the storage tank vertically. The vertically designed distributor could supply the return water with stratified temperature in the storage tank with respect to the height. The water velocity from the distributor hole is the same with the other outlet in the distributor. However, gravity effect on the flow in the storage tank is much higher than that of the velocity effect due to that Froude Number is less than 1. During the heat charging process in the storage tank, temperature maintained with little difference with respect to the height. However the charging process takes long time to get a effective temperature for the heating or hot water supply because of all of water in the storage tank needs to be heated.
Equilibrium Conditions of Methane Hydrate added Help Gases
Kim, Nam-Jin ; Lim, Sang-Hoon ; Chun, Won-Gee ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 51~58
Gas hydrate is a special kind of inclusion compound that can be formed by capturing gas molecules to water lattice in high pressure and low temperature conditions. When referred to standard conditions,
solid hydrates contain up to
of methane gas, depending on the pressure and temperature of production. Such large volumes make natural gas hydrates can be used to store and transport natural gas. In this study, three-phase equilibrium conditions for forming methane hydrate were theoretically obtained in aqueous single electrolyte solution containing 3wt% NaCl. The results show that the predictions match the previous experimental values very well, and it was found that NaCl acts as an inhibitor
Analysis of the Indoor Environmental Characteristics of Educational Facilities (Case Study of Thermal and Acoustical Environment of Elementary School by Field Measurement)
Cho, Min-Kwan ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 59~65
This study is to propose the basic data for deciding remodeling of wornout educational facilities. In order of it, the indoor environmental standard, the actual conditions of thermal environment and sound insulation of walls were examined through field measurement in the subjected open elementary school(J school) and modernization model of elementary school(Y school) which they are located in Seoul. As the result, standard for indoor environmental factors of educational facilities which is established by Ministry of Education is not subdivided into indoor environmental performances considering usages and characteristics of classrooms for comfortable indoor environment. The vertical temperature difference in general classroom and in open classroom showed to be
respectively, while indoor temperature of special classroon was, on the whole, higher than that of any other classroom due to its specific heat flux of wall materials. The sound insulation performance of the masonry brick wall of classroom satisfied the minimum standard of AIJ, Architectural Institute of Japan, in the open elementary school and the modernization model of elementary school. That is to say, the movable partition wall between the classroom and the corridor disturbed students in their class in the open school.
A Study of Thermal Performance Evaluation Index for Building
Kim, Mi-Hyun ; Suh, Seung-Jik ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 67~75
This study intends to the adequacy inspection of the room temperature variation rate that is available in the building heat performance evaluation index, so we performed the sensitivity analysis about the room temperature variation rate and the energy consumption in the room. For these purpose, we supposed the models which are composed of the various window area, insulation thickness and ventilation rate. Then we analyzed the simulation using the ESP-r and Seoul weather data. In this research, the pattern of the increasing & decreasing rate of annual load according to the change of the various design factors is similar to the pattern of increasing & decreasing rate of not the K-values but the room temperature variation rate. Also we derive the optimum value of the various design factors and the room temperature variation rate in this analysis model. Further study is to be required the development of convenient tool to use in the real design.
Comparison and Analysis of Domestic and Foreign Building Energy Rating Systems
Song, Seung-Yeong ; Lee, Soo-Jin ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 77~85
With the increase in the demand for sustainable and environment-friendly development all over the world, it becomes an urgent issue for Korea to reduce
emission. Since building industry accounts for about 40% of international energy and resource consumption and
emission, it is essential to prepare for energy-efficient building. This study aims to seek for improvement direction for a domestic Building Energy Efficiency Rating System through the comparison with foreign systems. Two foreign building energy rating systems which have the similar application scope with domestic one, HERS(Home Energy Rating System) and SAP(Standard Assessment Procedure)2005 were selected. As compared with foreign systems, we intended to suggest improvement direction for effective application of Building Energy Efficiency Rating System in Korea.
First and Second Law Analysis of Water-to-Water Heat Pump System
Lee, Se-Kyoun ; Woo, Joung-Son ; Ro, Jeong-Geun ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 87~95
Thermodynamic analysis of water-to-water heat pump system based on the first and second law of thermodynamics is carried out in this study. This analysis shows the distribution of irreversibilities throughout the system components and informs us of a potential improvements with the temperature condition changes. Source water temperature(
), utilization water temperature(
) and temperature differences (
) are important factors to affect system performances such as component irreversibilities, exergetic efficiency and COPH. Advantages and disadvantages with these factors are discussed. Second law optimization phenomena with
are also indicated.
Thermal Performance Study of Various Heat Pipe Working Fluid for Evacuated Tubular Solar Collector
Joo, Hong-Jin ; Kim, Jeong-Bae ; Kim, Jong-Bo ; Kwak, Hee-Youl ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 97~103
This study was carried out to compare the thermal performance and operating characteristics of evacuated tubular solar collector(ETSC) with different working fluid. The evacuated tubular solar collectors with different working fluid of heat pipe were investigated in the same operating condition for a indoor experiment equipment. First, the result of working fluid with Water showed that
was 0.6636 and
was -1.8457 Second, Ethanol showed that
was 0.6147 and
was -0.6365. Third, Flutec-pp9 showed that
was 0.515 and
was -3.2313. Finally MA's showed that
was 0.6572 and
An Experimental Study of a Water Type PV/Thermal Combined Collector Unit
Lee, Hyun-Ju ; Kim, Jin-Hee ; Kim, Jun-Tae ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 105~111
Hybrid PV/Thermal systems consisting of photovoltaic module and thermal collector can produce the electricity and thermal energy. The solar radiation increases the temperature of PV modules, resulting in the decrease of their electrical efficiency. Accordingly hot air can be extracted from the space between the PV panel and roof, so the efficiency of the PV module increases. The extracted thermal energy can be used in several ways, increasing the total energy output of the system. This study describes a basic type of PV/T collector using water. In order to analyze the performance of the collector, the experiment was conducted. The result showed that the thermal efficiency was 17% average and the electrical efficiency of the PV module was about
, both depending on solar radiation, inlet water temperature and ambient temperature.
Design and Preliminary Performance Test for 5kWt Dish Solar Collector
Seo, Joo-Hyun ; Ma, Dae-Sung ; Kim, Yong ; Seo, Tae-Beom ; Han, Gui-Young ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 113~120
The 5kWt dish solar collector is designed and the preliminary performance test for this is carried out. The diameter of the parabolic dish is 3.2 m, and its focal length is 2 m. It consists of 10 small reflectors which have their own curvatures, and the effective reflecting area is
, and the rim angle of the dish is
. The reflectivity of reflectors is 0.95, and the thermal capacity of the system is about 5 kW thermal. The aperture diameter of the cylindrical-shape receiver which is made of stainless steel is 100 mm, and the height is 210 mm. A quartz window is installed at the receiver aperture to minimize the convective heat loss and prevent air leakage. In order to increase the heat transfer area, porous materials (nickel-alloy) are inserted into the receiver. Air flows into the upper part of the receiver which is the opposite side of the aperture. After the air flows through the inside of the receiver, that goes out of the receiver through 3 exits which are located near the aperture. The volumetric flow rates of air are varied from 600 to 1200 L/min. The results show that the system efficiency and receiver efficiency increase as the volume flow rate increases
Convective Heat Loss from Solar Tower Receiver with Tilt Angles and Operating Conditions
Kang, Kyung-Mun ; Lee, Ju-Han ; Kim, Yong ; Seo, Tae-Beom ; Kang, Yong-Heack ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 121~128
Convective heat loss from solar tower receiver is experimentally investigated in wind tunnel with tilt angles and operating conditions. In order to simulate the receiver, an electric heater, which is made of aluminum (width : 100 mm, height : 100mm) is used and installed in the wind tunnel. The convective heat loss from the receiver is dependent on the direction and the velocity of the wind and the surface temperature of the receiver. The tilt angle and surface temperature of the receiver are varied from 0o (cavity facing straight down) and 90o(cavity aligned horizontally) and from
, respectively. Also, the wind speed is changed from 0 to 4m/s. The convective heat loss is obtained by measuring consumed power to the heater to maintain the desired surface temperature. It is concluded that Nusselt number increases with increasing wind speed for all cases. Especially, it is showed that Nusselt number can be maximized when the tilt angle is 30o.
Design, Fabrication and Performance Analysis of Fiber Optic Concentrators for Daylighting
Han, Hyun-Joo ; Kim, Jeong-Tai ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 129~136
Analysis of Passive Cooling Effect of Membrane Shading Structure and the Tree by Field Observations in the Summer
Choi, Dong-Ho ; Lee, Bu-Yong ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 137~146
This study is about the passive cooling effects of three outdoor solar shading facilities as trees, pergola with wistaria vine and membrane shading structure, which are expected to provide cool spots in the summer. Field observations of measuring thermal environment of selected facilities is executed. Thermal environment measuring was categorized as short wave radiation, long wave radiation, net radiation, globe temperature, surface temperature measured by infrared camera. Heat transfer mechanism is analyzed with overall data from field measurement. Results from this study are as below; 1) Radiation balance measured on shaded surface under membrane shading structure was 17%(
) of the unshaded surface radiation balance(
). 2) Surface temperature comparison between vegetation and membrane of the shading structure is performed at 3 o'clock in the afternoon. Surface temperature of vegetation was same as air temperature and that of membrane was
higher than air temperature. Vegetation transpiration is considered as the causing factor which make those differences. 3) Results from this study could be used as fundamental data for reducing heat island phenomena and continuos research on this subject would be needed.
A Study on the Implementation of Ubiquitous Technology for Residential Space
Han, Seung-Hoon ; Oh, Se-Kyu ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 147~155
It is essential to investigate the structure and the main characteristic of Home USN (Ubiquitous Sensor Network) technologies in built ubiquitous environment while designing future residential space. For this study, three different housing types have been selected to implement ubiquitous technologies for residential space; those are regular, elderly, and single residence units. It is certain that efficiency of ubiquitous home design is improved if main components of each specific housing type are analyzed precisely in digital way and design models are prepared accordingly. Ubiquitous technology, in conclusion, has to be applied not on)r with systematical mechanism or electronic setting but in human-centered atmosphere as well, keeping with deep consideration for bio-housing service factors in eco-friendly surrounding; we call this Ubiquitous Humanism.
Analysis of the Typical Meteorological Data and the Weighting Factor of TRY
Yoo, Ho-Chun ; Lee, Gwan-ho ; Park, So-Hee ; Kim, Kyoung-Ryul ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 157~165
Typical meteorological data is fundamental to computer simulation introduced for environment-friendly architecture designs. Therefore, in order to improve accuracy of computer simulation, typical meteorological data should be established. By examining how to choose typical meteorological data, this study selected the optimized weight factor for TRY where weighting factor was not clearly set. As a result, the same weighting factor was applied to each climatic element and TRY data where the weight factor was applied could have the distribution very similar to measurement data. The weighting factor is considered to reflect geographical characteristics of Seoul and applied climatic elements.
Analysis of Long-term Thermal Performance of Solar Thermal System Connected to District Heating System
Baek, Nam-Choon ; Shin, U-Cheul ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 167~173
This study analyzed by simulation using TRNSYS as well as by experiment on the solar district heating system installed for the first time for the district heating system in Bundang. Simulation analysis using TRNSYS focused on the thermal behavior and long-term thermal efficiency of solar system. Experiment carried out for the reliability of simulation system. This solar system where the circuits of two different collectors, flat plate and vacuum tube collector, are connected in series by a collector heat exchanger, and the collection characteristics of each circuit varies. Therefore, these differences must be considered for the system's control. This system uses variable flow rate control in order to obtain always setting temperature of hot water by solar system. Specifically, this is a system that heats returning district heating water (DHW) at approximately
using a solar collector without a storage tank, up to the setting temperature of approximately
To realize this, a flat plate collector and a vacuum tube collector are used as separate collector loops. The first heating is performed by a flat plate collector loop and the second by a vacuum tube collector loop. In a gross collector area basis, the mean system efficiency, for 4 years, of a flat plate collector is 33.4% and a vacuum tube collector is 41.2%. The yearly total collection energy is 2,342GJ and really collection energy per unit area (
) is 1.92GJ and 2.37GJ respectively for the flat plate vacuum tube collector. This result is very important on the share of each collector area in this type of solar district heating system.
Economic Estimation of Heat Storage Type Geothermal source Heat Pump System Adopted in Government office Building by a Payback Period Method
Ko, Myung-Jin ; Oh, Jung-Keun ; Kim, Yong-In ; Kim, Yong-Shik ;
Journal of the Korean Solar Energy Society, volume 27, issue 4, 2007, Pages 175~182
Geothermal-energy has been getting popular as a natural energy source for green buildings these days. As a result Geothermal Source Heat Pump System (GSHPs) was being recognized effective alternative systems to conventional heating and cooling systems owing to their higher energy utilization efficiency. But GSHPs has not been popularized thereby the large amount of initial cost of the system and insufficiency of studies for economic estimation. Therefore GSHPs are being developed to make up for the weak points that are the large amount of initial cost of the system and much annual electricity consumption. In this paper, economic estimation was conducted by payback period method and it shows that the pay back period of Heat Storage Type GSHPs was calculated 6.8 years compared with the absorption Chiller-Heater system and 8.2 years compared with the Ice storage-Boiler system. Heat Storage Type GSHPs also has the lower annual source energy consumption than the conventional heating and cooling systems because of using nighttime electricity.