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 32, Issue 6 - Dec 2012
Volume 32, Issue 5 - Oct 2012
Volume 32, Issue 4 - Aug 2012
Volume 32, Issue spc3 - Jun 2012
Volume 32, Issue 3 - Jun 2012
Volume 32, Issue 2 - Apr 2012
Volume 32, Issue 1 - Feb 2012
Selecting the target year
Manufacturing of an FBG sensor imbedded small wind turbine blade
Kim, Chang-Hwan ; Yun, Jin-Young ; Kim, Hyun-Gyu ; Kim, Kwan-Soo ; Paek, In-Su ; Yoo, Neung-Soo ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 1~8
DOI : 10.7836/kses.2012.32.4.001
A Fiber Bragg Grating (FBG) sensor imbedded small wind turbine blade was manufactured to experimentally investigate the feasibility to embed FBG sensors between layers of glass fiber to monitor dynamic strains of the wind turbine blade. The blade which is similar to a commercial 300 W wind turbine blade was manufactured with glass fiber as a reinforcement and epoxy resin as base material. A total of five FBG sensors including one temperature sensor were imbedded in the blade to sense mechanical strain and temperature. While manufacturing the blade, residual strain and temperature that occurred in the small wind turbine blade were monitored using the imbedded FBG sensor array. To examine the sensor performance, an impact test was carried out. The experimental results from the FBG sensors were close to those from electrical strain gages mounted on the blade root surface. The mode shapes of the blade were analyzed also using a commercial Ansys simulation with a model obtained from a three dimensional laser scanning of the blade.
Study on the Thermal Conductivity and Viscosity of Ethanol with Carbon Nanotubes for the Development of a Heat Pipe Working Fluid
An, Eoung-Jin ; Park, Sung-Seek ; Park, Yoon-Chul ; Kim, Jong-Yoon ; Kim, Nam-Jin ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 9~16
DOI : 10.7836/kses.2012.32.4.009
Nanofluids using Carbon Nanotubes have a excellent thermal characteristic. In this study, for increasing the efficiency of solar collector, the thermal conductivity and viscosity of Ethanol-Oxidized Multi-walled Carbon Nanofluids were measured. Nanofluids were manufactured by ultra-sonic dispersing Oxidized Multi-walled Carbon Nanotubes(OMWCNTs) in ethanol at the rates of 0.0005 ~ 0.1 vol%. The thermal conductivity and viscosity of manufactured nanofluids were measured at the low temperature(
), the room temperature(
) and the high temperature(
). For measuring thermal conductivity and viscosity, we used transient hot-wire method and rotational digital viscometer, respectively. As a result, under given temperature conditions, thermal conductivity of the 0.1 vol% nanofluids improved 33.74% (
), 33.14% (
) and 32.36% (
), and its viscosity increased by 37.93% (
), 31.92% (
) and 29.42% (
) than the base fluids.
A Study on the Effect of Wind Turbulence Intensity on the Power Performance of Wind Turbine System
Hyun, Seung-Gun ; Ju, Young-Chu ; Kim, Keon-Hoon ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 17~23
DOI : 10.7836/kses.2012.32.4.017
The installed capacity of wind turbines in Korea are growing and enlarging by the central government`s supporting program. But the majority area having the abundant wind energy resources is composed of mountainous and complex district, thus the turbulence intensity of there is so high and belongs to the turbulence characteristic A category of IEC design requirement. This paper presents the effect of the turbulence intensity on the power performance of a wind turbine system. Particularly, the effect of the power curve of the wind turbine system due to the turbulence intensity has analyzed. As a result, the power curve has a high turbulence characteristic shows the lower value than normal one in high wind speed regime and the AEP will be reduced at the relatively high turbulence area.
Annual Base Performance Evaluation on Cell Temperature and Power Generation of c-Si Transparent Spandrel BIPV Module depending on the Backside Insulation Level
Yoon, Jong-Ho ; Oh, Myung-Hwan ; Kang, Gi-Hwan ; Lee, Jae-Bum ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 24~33
DOI : 10.7836/kses.2012.32.4.024
Recently, finishing materials at spandrel area, a part of curtain-wall system, are gradually forced to improve thermal insulation performance in order to enhance the building energy efficiency. Also, Building Integrated Photovoltaics(BIPV) systems have been installed in the exterior side of the spandrel area, which is generally composed of windows. Those BIPVs aim to achieve high building energy efficiency and supply the electricity to building. However, if transparent BIPV module is combined with high insulated spandrel, it would reduce the PV efficiency for two major reasons. First, temperature in the air space, located between window layer and finishing layer of the spandrel area, can significantly increase by solar heat gain, because the space has a few air density relative to other spaces in building. Secondly, PV has a characteristics of decreased Voltage(Voc and Vmp) with the increased temperature on the PV cell. For these reasons, this research analyzed a direct interrelation between PV Cell temperature and electricity generation performance under different insulation conditions in the spandrel area. The different insulation conditions under consideration are 1) high insulated spandrel(HIS) 2) low insulated spandrel(LIS) 3) PV stand alone on the ground(SAG). As a result, in case of 1) HIS, PV temperature was increased and thus electricity generation efficiency was decreased more than other cases. To be specific, each cases` maximum temperature indicated that 1) HIS is
, 2) LIS is
, and 3) SAG is
. Also, each cases yield electricity generation like that 1) HIS is 913.3kWh/kWp, 2) LIS is 942.8kWh/kWp, and 3) SAG is 981.3kWh/kWp. These result showed that it is needed for us to seek to the way how the PV Cell temperature would be decreased.
The Suggestion and application of the Evaluation Method for Selecting Energy Plant on City Planning Step
Park, Jin-Young ; Park, Tool ; Yee, Jurng-Jae ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 34~42
DOI : 10.7836/kses.2012.32.4.034
The forecasted energy shortage tends to encourage to develop the next generation energy to countermove the energy problems and the climatic change all over the world. Korean government is pushing ahead with the policy for `Low Carbon Green Growth` to deal with climate changes and to overcome energy problems. And many studies for low carbon green city or zero carbon city have been progressed. In this study, energy plants and energy scenarios are selected by energy supply suited features of city at city plan. The method to evaluate energy scenario can be proposed to apply various energy plants for energy demand on city planning step and evaluation method can be systematized to be used by users. Also the calculated values are changed into index for comparison according to each energy scenario.
Performance Evaluation of Selective Coatings for Solar Thermal Collectors
Lee, Kil-Dong ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 43~50
DOI : 10.7836/kses.2012.32.4.043
Metal-metal oxide (M-M oxide) cermet solar selective coatings with a double cermet layer film structure were deposited on the Al-deposited glass substrate by using a directed current (DC) magnetron sputtering technology. M oxide (CrO and ZrO) was used as the ceramic component in the cermets, and Cr and Zr used as the metallic components. In addition, black Cr (Cr-
cermet) solar selective coatings were deposited on the Ni-plated Cu substrate by using a electroplating method for comparison. The thermal stability tests were carried out for performance evaluation of solar coatings. Reflectance measurements were used to evaluate both solar absorptance(
) and thermal emittance (
) of the solar coatings before and after thermal testing by using a spectrometer. Optical properties of optimized cermet solar coatings were
). The results of thermal stability test of M-M oxide solar coatings showed that the Cr-CrO cermet solar selective coatings were more stable than the Zr-ZrO cermet selective coatings at temperature of both
in air and
in vacuum. The black Cr solar selective coatings were degraded in air at temperature of
. The main optical degradation modes of these coatings were diffusion of metal atoms, and oxidation.
Temperature and Power Generation Characteristics of c-Si G/G Spandrel Window depending on Opening Ratio of PV Module
Yoon, Jong-Ho ; Kim, Dong-Su ; Oh, Myung-Hwan ; Lee, Jae-Beom ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 51~58
DOI : 10.7836/kses.2012.32.4.051
This study aims to analyze characteristics of Cell surface temperature and generated power performance for improving PV(Photovoltaic) system condition according to the cell opening ratio of transparent crystal PV system at Spandrel of curtain-wall. For this purpose, alternatives were classified for eight different cases that opening ratio of transparent crystal PV system varied from 0% to 70%, which was used by simulation tool, EnergyPlus. As results, it turned out that increasing opening ratio of transparent crystal PV system led higher PV surface temperature, back-sheet type was thus the most advantageous for decreasing surface temperature, annual generating efficiency, and annual accumulated generating power. Consequently, blocking off air space from outside insolation can advantageously keep to be better condition for generated power performance.
Analysis on Design Parameters of Small Hydropower Sites with Rainfall Conditions
Lee, Chul-Hyung ; Park, Wan-Soon ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 59~64
DOI : 10.7836/kses.2012.32.4.059
The correlation between hydrologic performance design parameters of small hydro power(SHP) sites and rainfall condition have been analyzed for major river systems. The model, which can predict flow duration characteristic of stream, was developed to estimate the inflow caused from rainfall. And another model to predict hydrologic performance for SHP plants is established. Based on the models developed in this study, the hydrologic performance characteristics for SHP sites have been analyzed. The results show that the hydrologic performance characteristics of SHP sites have some difference between the river systems. Especially, the specific design flowrate and specific output of SHP sites located on North Han river and Nakdong river systems have large difference compared with other river systems. It was found that the hydrologic performance design parameters such as specific design flowrate and specific output were affected by rainfall condition in basin area of SHP sites.
Evaluation of the Energy Efficiency Rating in small office building according to the Thermal Performance of Building Envelope
Kim, Sang-A ; Hong, Won-Hwa ; Park, Hyo-Soon ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 65~70
DOI : 10.7836/kses.2012.32.4.065
Each country has implemented various environmental policies to prevent natural disasters and destruction of ecosystem caused by global wanning. The republic of Korea also was performed building energy efficiency rating certification system as part of paradigm of `Low carbon green growth` since 2010. However, the status on the building energy efficiency rating certification system has not been analyzed. In this study, We analyzed the elements affecting the energy efficiency of small office buildings focusing the status and certification cases of the building energy efficiency rating system. As a result, it is judged that thermal performance contribution of the building envelope is not high in the buildings certificated the first grade of the building energy efficiency rating system.
Observation and Analysis of the Long and Short Wave Radiation According to Different Altitudes and Locations in Daegu During Summer
Choi, Dong-Ho ; Lee, Bu-Yong ; Oh, Ho-Yeop ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 71~81
DOI : 10.7836/kses.2012.32.4.071
This study for the understanding of the radiation environment according to the altitude in urban area in the summer observes the long and short wave radiation environment at the 4 urban areas with different height and the 1 suburban area. The results of this study are as follows. (1) When the altitude was high, the more short wave radiation was observed. (2) As the altitude was high, the temperature of atmosphere got lower. And because of that the downward long wave radiation was also lower. This general trend was confirmed through the study. (3) Through the observation of long wave radiation, the upper atmosphere of suburban area had the atmosphere characteristic which the temperature was rising and decreasing faster. Therefore, the difference radiation characteristics between the urban and suburban area were confirmed. (4) The result of the ratio of short wave radiation to long wave radiation(short wave radiation/long wave radiation) according to the altitude and location, the value was increased when the distance was far from the artificiality structure or a heat source, and the urban effect became smaller. Thus, it is expected that the ratio will be an evaluation index for evaluating urbanization effect.
A Thermal Flow Analysis for an Optimal shape of Solar Lamp Bank
Baek, Sang-Hwa ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 82~89
DOI : 10.7836/kses.2012.32.4.082
This study is on the thermal flow analysis to select an optimal shape of solar lamp bank. Solar Lamp bank is designed by the lamp bank design program based on point light source theory. The reliability of the program for lamp bank design is verified through irradiance variation experiments of a kind of lamp according to horizontal distance. Solar lamp bank facilitates heat distribution and satisfies the irradiance in the three wave length which test guidelines require. Among the 4 kinds of lamp bank, since lamp bank type D satisfies uniformity
and also doesn`t exceed total irradiance 1,232
, type D is finally selected.
A Case Study of Electric Power Consumption Characteristics in University Building
Lee, Wang-Je ; Lee, Dong-Won ; Lee, Jae-Bum ; Yoon, Jong-Ho ; Shin, U-Cheul ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 90~95
DOI : 10.7836/kses.2012.32.4.090
Of school buildings, university building requires various case analysis unlike buildings in the elementary, middle and high schools in accordance with its characteristic for variables such as characteristic of department, construction structure and material, the number of persons admitted and schedule. Through the case research on the `D` university located in Daejeon, this study made a comparison on the monthly and yearly consumption of gas and electricity of the most recent 3 years and implemented analysis on the usage pattern and standby power of air conditioning and heating by the hour and month using PCCS(Power Consumption Consulting System) as respects electricity that is considered to have a possibility of energy-saving. The result of analysis showed that enormous amount of electric power was used during the night time for freeze protection and burst in winter season and standby power was increased in winter season as a result.
A Study on the Comparison Analysis of Minimum Airflow Control Logic of VAV Terminal Box
Cho, Young-Hum ; Kang, Su-Hyun ; Seong, Yoon-Bok ;
Journal of the Korean Solar Energy Society, volume 32, issue 4, 2012, Pages 96~102
DOI : 10.7836/kses.2012.32.4.096
The minimum airflow of VAV terminal boxes is a key factor for comfort, indoor air quality(IAQ) and energy cost. If the minimum airflow is not reasonable, it would waste energy and make IAQ problems. There are two types of VAV terminal box control logic. One is the single maximum, another is the dual maximum control logic. Dual maximum control logic is more efficiency way to reduce the energy consumption. It has a minimum airflow set point and a heating maximum set point. It allows the minimum airflow set point to be much lower than single maximum control logic. A building simulation was conducted to evaluate the energy consumption and the IAQ according to the control logic of the V AV terminal box. In the simulation, dual maximum control logic can save the energy up to 6.5% compared to the single maximum control logic.