• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1442-1442
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• 2011

Increase the cost of electricity generation compared to (30 million won / KW) can only be used in standalone or distributed, but in the same area of photovoltaic conversion efficiency is much higher than with a large Stirling engine development has economic value of the infinite. Commercialization 25KW level or above Stirling engine production or introduction is necessary solar power in the various application and effect analysis for further empirical studies or regional energy projects, demonstration of business expansion and conductor, Stirling engines.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.157-160
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• 2006

The Dish/Stirling system with the Stirling engine is currently used to convert solar energy directly to electrical energy successful operation of dish/Stirling system is supported by hybrid system, which will allow continuous operation driven by solar and combustion heat ins. The hybrid Receiver has to be provided with an additional combustion system. The heat pipe receiver and conbustion system were manufactured and tested for thermal characteristics of receiver. Maximum temperature difference along the heat pipe surface is $200^{\circ}C$. Emission measurements showed low NOx values of 28 to 46 ppm and very high CO values of 18 to 201 ppm.

• 한국신재생에너지학회:학술대회논문집
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• 2005.11a
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• pp.684-687
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• 2005

KIER has been running a demonstration project for 10kWe solar thermal power generation. the project is to build and operate the first solar thermal power generation system in Korea. For concentrating solar thermal energy $40m^2$ dish type concentrator was adapted and a stirling engine is going to be integrated to the system for power production. At the moment building the dish concentrator including mirror and sun tracking system was completed and it's performance are being closely evaluated. This paper will introduce some detailed designs and construction procedures which we have experienced so far.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.397-403
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• 2007

In this paper, conceptual design of scroll expander-compressor for Stirling engine utilizing solar energy as heat source has been carried out. Orbiting scroll member was designed to have a double-sided structure to reduce the overall scroll size and to cancel out the axial forces on the orbiting scroll base plate. Diameter of designed scroll base plate was about 251 mm for the expander, and it was about 218 mm for the compressor. With operating condition such as temperature range of $400^{\circ}C/20^{\circ}C$, pressure range of 6 MPa/2 MPa, and shaft speed of 2700 rpm, the shaft output of the designed scroll expander was calculated to be 49.8 kW, while input power for the scroll compressor was 38.6 kW, yielding 11.2 kW for the output power of the Stirling engine. Overall efficiencies of the scroll expander and compressor were 93.73% and 92.87%, respectively.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.2
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• pp.94-102
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• 2009

Conceptual design of scroll expander and scroll compressor for 10kW-class Stirling engine utilizing solar energy as heat source has been carried out to estimate the applicability of scroll mechanism for Stirling cycle. CO2 was chosen as working fluid, since it has lower expansion index and higher density among probably usable gases. Gas temperature at the expander inlet was set at $700^{\circ}C$, and that at the compressor inlet was at $40^{\circ}C$. System efficiency reached maximum at the pressure ratio of about 2.5, and the peak efficiency increased with increasing high side pressure. Due to safety concern, the pressure condition of 6 MPa/2.5 MPa was chosen as design condition. Orbiting scroll members for the expander and compressor were designed to have double-sided structure in order to reduce the overall scroll size and to cancel out the axial gas forces acting on the orbiting scroll base plate. By parametric study on the scroll profile, smaller possible size for the scroll members was obtained. With the shaft speed of 3600rpm, the shaft output of the designed scroll expander was calculated to be 45.4kW, while input power for the scroll compressor was 34.5kW, yielding 10.9kW for the output power of the Stirling engine. System efficiency was estimated to be about 7.3%, and overall efficiencies of the scroll expander and compressor were around 84.1% and 88.3%, respectively.

• Journal of the Korean Solar Energy Society
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• v.37 no.2
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• pp.59-66
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• 2017

This paper compares the output power of different types of small Stirling engines in conjunction with the utilization of low grade thermal energy. A series of experimental measurements were performed to assess the output power of each engine under different conditions of the temperature difference between the hot and cold ends as well as applied weight. Results are presented in terms of torque and output power per heat transfer area. Among tested, the MM-7 engine produced the highest power of 4.455mW ($321mW/m^2$) under a temperature difference of $40^{\circ}C$.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.571-575
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• 2006

To improve economic of solar power generation, stirling engine is required continuous operation and the receiver has to be provided with an additional combustion system. The hybrid receiver with a specially adapted combustion system is possible to 24 hr/day operation by solar and gas-fired. The inner cavity and external wall serve as absorber surfaces using collected irradiation and heat transfer surfaces for the gas heat flow, respectively. The hybrid receiver was designed and fabricated for the dish/stirling system. The analytical method for pridicting natural convective heat loss from receiver is used. The Koenig and Marvin model is used to estimate convection heat loss and heat transfer coefficiency.

• Design & Manufacturing
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• v.13 no.1
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• pp.19-24
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• 2019

Currently, the world is paying keen attention to the production of renewable energy along with environmental issues, and the share of renewable energy in the world is rising above that of nuclear power. Especially when Korea, which is heavily dependent on foreign countries, needs to reconsider its national competitiveness due to the recent high oil prices, the government's energy policy is to develop and use renewable energy that replaces fossil fuels. In particular, solar energy, the most actively studied and commercialized field of renewable energy, is the main research for solar energy and is commercialized and used. However, the efficiency of solar energy has already reached saturation. Studies are also focusing on increasing the reflectivity of solar energy to increase efficiency. Therefore, this paper proposes a solar collection system that can utilize solar energy rather than solar energy. The proposed solar heat collection system uses solar tracking systems to effectively collect solar energy, particularly those that can be easily produced using single-modular reflectors and have price competitiveness. In addition, temperature measurement experiments with temperature measuring sensors were conducted to ensure reliability in order to verify the results interpreted.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.668-671
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• 2007

A numerical study was conducted on a simplified model of a high-temperature solar receiver which incorporates liquid-metal heat pipe. The objective of this paper is to compare the isothermal characteristics of the heat pipe receiver with the conventional receiver utilizing convection of molten salt as heat carrier. The solar receiver was assumed to be subject to a concentration ratio between 50 and 1,000 to supply high-temperature heat to a stirling engine for electric power generation. For simplicity of the analysis, a cylindrical geometry was assumed and typical dimensions were used based on available literature. The heat pipe had a shape of double-walled cavity and the working fluid was a sodium. The analysis was performed assuming that the radiation heat flux on the inner walls of the receiver was uniform, since the focus of this study was laid on the comparison of the conventional type and heat pipe type receiver. The results showed that the heat pipe type exhibited superior performance when the operating temperature becomes higher. In addition, to explore the advantage of the heat pipe receiver, the channel shape and dimensions should be adjusted to increase the heat transfer area between the wall and the heat trnasfer medium.

• Proceedings of the KAIS Fall Conference
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• 2012.05b
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• pp.559-561
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• 2012

현대 사회의 중요 자원인 전기는 총생산량 중 90%이상이 화력발전과 원자력 발전에 의존하고 있으나, 최근 화석 연료의 급격한 가격 상승과 환경오염에 대한 중요성이 대두 되면서, 그린에너지 연구에 대한 관심이 급증하고 있다. 이러한 연구의 일환으로 본 연구에서는 태양에너지의 이용효율을 높일 수 있는 시스템 개발 기술에 초점을 맞추어 연구를 진행하였다. 열효율이 좋은 스털링 엔진을 구동하는 열원으로 태양열을 이용하고, 엔진에 발전 시스템을 결합시켜 전기를 생산할 수 있는 소형 태양열 발전 시스템을 제작하였다. 제작된 시스템으로 기초실험을 수행하여, 기술의 실용성을 평가하였다. 본 연구에서 제작한 시스템에서 155 mW의 전기를 발전할 수 있었으나, 시스템의 최적 설계 시 더 높은 출력을 얻을 수 있는 기술이라 예상한다.