• Proceedings of the KSME Conference
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• 2005.11a
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• pp.15.1-15.1
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• 2005

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.3 no.4
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• pp.263-275
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• 1991

Studies on the annual performance of three different type of solar-absorption heat pump system (parallel type, series type, and generator type) are carried out by using the computer simulation. These include the calculation of solar energy from the solar collector, and the revision of computer package, developed by Oak Ridge National Laboratory, to predict the annual performance. Finally using weather data and load conditions, the annual performance are obtained. Results show that the annual operating costs of three solar-absorption heat pump systems are almost same values and 44% lower than that of the pure absorption heat pump system. The total annual input energys of solar-absorption heat pump systems are also about 44% lower than that of the pure absorption heat pump. The nominal size of the solar-absorption heat pump systems can be reduced to a value of 55% that of the pure absorption heat pump that would normally be specified under identical conditions.

• KIEAE Journal
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• v.9 no.4
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• pp.37-42
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• 2009

Photovoltaic-thermal(PVT) collectors are a combination of photovoltaic modules with solar thermal collectors, forming one device that receives solar radiation and produces electricity and heat simultaneously. The PVT collectors can produce more energy per unit surface area than side by side PV modules and solar thermal collectors. There are two types of water type PVT collectors, depending on the existence of glass cover over PV module; glass-covered(glazed) PVT module, which produces relatively more thermal energy but has lower electrical yield, and uncovered(unglazed) PVT module, which has relatively lower thermal energy with somewhat higher electrical performance. In this paper, the experimental performance of two types of the water-based PVT combined collectors, glazed and unglazed, was analyzed. The electrical and thermal performances of the PVT combined collectors were measured in outdoor conditions, and the results were compared.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.4
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• pp.129-139
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• 2010

This paper presents a basic energy performance data of microturbine, renewable Energy(BIPV and Solar Collector System) and a hybrid energy system(geothermal system and microturbine) installed in hospital building. The efficiency of solar collector and BIPV system was 30[%], 10[%] individually, and lower than micro turbines. Finally, in energy performance aspect, microturbine and geothermal source heat pump system were a high-efficiency system in hospital building. It is confirmed hybrid energy systems also show the most powerful alternative energy system for green hospital building from the simulation results.

• Applied Biological Chemistry
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• v.26 no.2
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• pp.75-81
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• 1983

The performance of the flat-plate solar collector with rock-pile thermal storage medium and the drying characteristics of rough rice and red pepper by use of natural air and of supplementary heated air by the solar drier were studied. The thermal efficiency of the flat-plate solar collector was average 25.4 percent and the overall heattransfer coefficient of the collector was approximately $38.13kJ/hr.m^2^{\circ}C$. The flat-plate collector was able to supply the supplementary heated air which was about $7^{\circ}C$ higher than the ambient air temperature during the daytime and about $3^{\circ}C$ higher than during the night. For rough rice drying of grain moisture content front 24.5 to 14.5%, it took 18 days in the natural air system, 12 days in the tubular solar collector and 10 days in the flat-plate solar collector. For red pepper drying from it's moisture from 81.0 to 15.0%, 68 hrs required under conventional sun drying system, but 38 hrs in tubular solar collector and 36 hrs in the flateplate solar collector. The changes of capsanthin and capsaicine content were investigated at various drying system, and little difference was found among the drying system.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.768-773
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• 2009

A numerical study has been performed to investigate the thermal Performance of Solar heating system with baffle type of storage tank by using the commercial code TRNSYS. As a result, the solar fraction depends strongly on the efficiency and heat loss coefficient of solar collector as well as the heating capacity of house and the water temperature supplied to the shower. In addition, the solar fraction has been basically ranked to higher level in baffle type of storage tank than typical type of single storage tank for the range of operation condition.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.11
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• pp.805-811
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• 2010

A numerical study has been performed to investigate the thermal performance of solar heating system with baffle type of storage tank by using the commercial code TRNSYS. As a result, the solar fraction depends strongly on the efficiency and heat loss coefficient of solar collector as well as the heating capacity of house and the water temperature supplied to the shower. In addition, the solar fraction has been basically ranked to higher level in baffle type of storage tank than typical type of single storage tank for the range of operation condition.

• 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 Advanced Marine Engineering and Technology
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• v.37 no.4
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• pp.316-323
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• 2013

The use of artificial roughness in various forms of shapes and sizes is the most common and effective way to improve the performance of a flat-plate solar collector. In the present study, numerical analysis on heat transfer and pressure drop was performed in a rectangular channel with various rib arrays. The uniform heat flux is applied to the channel from the upper side. The forms of ribs considered in this study were rib $90^{\circ}$, groove $90^{\circ}$, groove $60^{\circ}$, baffle $90^{\circ}$, baffle $60^{\circ}$, wave $90^{\circ}$ and wave $60^{\circ}$. Air is the working fluid, and the Reynolds number ranges from 3200 to 17800. Nusselt number and friction factor were investigated to predict the performance of the system with various type of ribs. The average Nusselt number and pressure drop were increased with the increase of velocity in all types of ribs. The highest heat transfer and pressure drop occurred for the baffle $90^{\circ}$, but highest performance factor considering heat transfer and pressure drop together occurred for the groove $60^{\circ}$. Therefore, heat transfer and pressure drop should be considered together when a flat plate solar collector is designed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.4
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• pp.260-265
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• 2008

The excess heat that is generated from PV modules can be removed and converted into useful thermal energy. A photovoltaic/thermal (PVT) module is a combination of photovoltaic module with a solar thermal collector, forming one device that converts solar radiation into electricity and heat simultaneously. In general, two types of PVT can be distinguished : glass-covered PVT module, which produces high-temperature heat but has a slightly lower electrical yield, and uncovered PVT module, which produces relatively low-temperature heat but has a somewhat higher electrical performance. In this paper, the experimental performance of water type PVT combined module, glass-covered, analyzed. The electrical and thermal performance of the module were measured in outdoor conditions, and the results are analyzed. The results showed that the thermal efficiency of the PVT module was 27.6% average and its PV efficiency was about 10.0% average, both depending on solar radiation, inlet water temperature and ambient temperature.