• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.830-830
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• 2015

최근 기존 도시철도역사의 환기 설비 노후화로 인해 성능과 효율이 저하되고 있다. 또한, 상황에 따른 요구 환기량을 반영하여 풍량 조절이 불가해 효과적인 환기가 이루어지지 못하고 있다. 지구온난화로 인한 기후변화에 따른 냉 난방시설의 전력 소비 증가와 화석연료의 고갈로 전력 단가가 상승함으로써 에너지효율을 높일 수 있는 방법이 연구되고 있다. 에너지 효율을 높일 수 있는 방법으로 높은 고효율 영구자석 전동기를 포함한 블로워의 도입에 대한 방안과 기존 환기설비의 on/off제어에서 가변속 운전방식에 따른 방안이 관심을 받고 있다. 본 논문은 가변속 운전 방식의 도입이 미치는 영향검토를 위해 가변속 운전 방식의 도입에 대한 에너지 절감효과를 예측하고, 기존설비와의 효율을 비교하고 검토할 수 있는 MATLAB 기반의 프로그램을 제안한다. 본 논문은 MATLAB 시뮬레이션 결과를 바탕으로 블로워 전동기 가변 속 운전방식에 대한 소비전력량 차이를 입증하였다.

• Journal of the KSME
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• v.29 no.1
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• pp.40-47
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• 1989

신형안전로 개발의 필요성을 설비개발이라는 관점에서 우리가 해결해야 할 과제로 요약하면 첫 째는 설계개념이다. 즉 어떠한 설계개념을 채택하여야만 설비의 단순화가 가능하며 중소형이 면서도 경제성 확보가 가능할 것인가 하는 점이며, 둘째는 이러한 새로운 개념은 과연 원전의 안전성이 혁신적으로 개선된 것이며, 어디에나 용이하게 건설이 가능토록 부지요건이 완화된 것이며, 전문가가 아닌 사람도 용이하게 운전가능토록 준 무인운전 수준의 편의성 확보가 가능 한가 하는 점이다. 셋째는 극히 소용량인 지역난방 원자로에서부터 대용량 발전 설비에 이르 기까지의 연계 개발 계획으로서 수요처별 수요 적응 특성 반영과 Modular Type 또는 기타의 방법으로 용이하게 용량을 확장할 수 있는 방법을 강구하는 문제이다.

• Plant Journal
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• v.10 no.3
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• pp.45-51
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• 2014

This study performs several experiments on a newly developed temperature safety system that can be used for residential building heating systems, the heat source of which is derived from a conventional fuel cell. Prior to this, the hot water made from a fuel cell was not used in residential housing but just went to waste. The present safety system is installed in the current underfloor heating system. At first we used the CFD technique to develop a new heat exchanger. The fuel cell must satisfy the thermal conditions of the inlet temperature being $55^{\circ}C$ and the outlet temperature being $60^{\circ}C$. But variations in weather cause fluctuations in the heating water temperature. The experimental results show our new system capable of maintaining the temperature difference within a ${\pm}0.5^{\circ}C$ range. So we believe that our new PFMFC fuel cell stack array is a good candidate for being used in residential heating systems.

• Journal of Energy Engineering
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• v.28 no.3
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• pp.18-25
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• 2019

In this study, in order to solve the problem of the program of calculating code input by experienced users in the power generation, the wide area energy network research group developed the local heating operation analysis program EntPLAN, which can be easily used by anyone, including scalability, with domestic technology. Therefore, the Commission intended to compare the heat sources, heat demand, and the results of operation of the combined heat plant (CHP) on the energy network through simulation with the EnetPLAN and the program A on the market. The results showed that the heat and power output on the energy network of the EnetPLAN and A programs were mostly similar in pattern in the simulation results of the heat supply and the operation method of the accumulator. This enabled the application of the simulation for the various operation modes of the cogeneration facilities existing on the energy network. It is expected that EntPLAN, which was developed with domestic technology, will be easily applied in the field in the future and will present efficient operation simulation results.

• Journal of Energy Engineering
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• v.7 no.1
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• pp.81-88
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• 1998

This paper describes the method decide to optimal sizing and operation scheduling of total cogeneration system which is interconnected with cogeneration unit of utility and auxiliary thermal devices of heating company. Optimal sizing and operation scheduling is established in order to minimize the fuel cost under national viewpoint. Simulations are carried out to show the reliability of method suggested by seasons and kinds. The simulated results can be effectively used as the guideline of operation scheduling between the utility and the heating company.

• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.121-121
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• 2003

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.212-212
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• 2004

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.145-145
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• 2004

• JOURNAL OF ELECTRICAL WORLD
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• no.8 s.92
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• pp.82-85
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• 1984

지루한 장상로부터 여름에 걸쳐서 빼놓을 수 없는 것이 쿠울러이다. 단순히 냉방, 제습뿐만이 아니라 한 이로 난방도 할수 있는 것이 피이트펌프식 에어콘이다. 또 작금은 성에너지를 도모하여 주위의 환경에 맞추어 이상적인 운전은 가능케한 인버어터탑재형에어컨도 각광을 받고 있다. 여기서는 왜 피이트펌프식인가? 왜 인버어트식인가에 대해서 알아보는 동시에 설치상의 문제점에 대해서 생각해보기로 한다.

• Journal of Energy Engineering
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• v.17 no.2
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• pp.116-123
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• 2008

In order to study the heat transfer, effectiveness and pressure drop of an internal heat exchanger (IHX) for $CO_2$, heat pump under heating condition, the experiment and numerical analysis were performed. Four kinds of IHXs were used. The section-by-section method and Hardy-Cross method were used for the numerical analysis. The effects of IHX on the flow rate of refrigerant, the IHX length, the operating condition of a gas-cooler and an evaporator and the type of IHXs were investigated. With increasing the flow rate, the heat transfer rate increased about 25%. The heat transfer of the micro-channel tube was larger about 100% than that of the coaxial tube. With increasing the IHX length, the heat transfer rate decreased. The low-side pressure drop was larger compared with that of the high-side. And the pressure drop of the microchannel tube was larger about 100% than that of the coaxial tube. With increasing the high-side temperature and decreasing the low-side temperature, the heat transfer rate increased about 3%. From this study, we can see that new correlation on $CO_2$ heat transfer characteristics and tube type is necessary.