• 에너지공학
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• 제20권4호
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• pp.330-337
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• 2011

난방장치로서 통상 가스 및 기름보일러가 많이 사용되어진다. 본 연구는 기존의 가스 및 기름 보일러에 의한 난방방식과 달리 밀폐된 X-L 파이프 내에 특수 제작된 전열선을 삽입하여 그 전열선에 전압을 인가함으로써 X-L 파이프 내 열매체의 온도를 상승시켜 난방하는 방법에 관한 것이다. 특수 제작된 전열선의 가닥수와 인가전압을 변화시켜 X-L 파이프 보일러의 특성과 발열 메카니즘을 파악하였다. 또한 X-L 파이프 보일러와 가스 및 기름보일러와의 난방비용을 객관적인 자료에 근거하여 서로 비교를 함으로써 그 경제성을 평가하였다. 그 결과 X-L 파이프 보일러는 기름(보일러등유)보일러의 28%, 가스(천연가스)보일러의 58%의 비용으로 난방이 가능함을 확인하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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• pp.908-912
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• 2003

The waste heat recovery system using heat pipe was tested for the consideration of developing the high-efficiency waste heat recovery technology. Heat pipe, a effective device that can quickly transfer large amounts of heat energy using the phase change of the working fluid and the characteristics of Electric Heater Bars used for alternative heating system are introduced In this paper. In order to increase energy efficiency, the system which controls the status of electric heater bars and the temperature of heat pipe installed has developed.

• 한국수소및신에너지학회논문집
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• 제22권4호
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• pp.546-551
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• 2011

The corrosion on steam generator tubes of the secondary side of pressurized water reactor inhibits heat transfer. One of the most efficient techniques improving the heat transfer performance of a nuclear electric generation is a corrosion control. The environmental parameters mostly affecting corrosion are materials and chemical additives. It seems that no further corrosion occurs in steels with Polyacrylic acid polymer dispersant treatment. Polyacrylic acid forms a protective coating with uniform thickness on metal surface. Polyacrylic treatment appears to be the most convenient way to enhance the thermal performance by the thermal conductivity improvement in steam generators.

• 한국수소및신에너지학회논문집
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• 제34권6호
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• pp.773-784
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• 2023

In this study, a comparative analysis between an electric heat pump cooling system and a hybrid desiccant cooling system is conducted. Desiccant cooling is a thermal driven system with potentially lower electric power consumption than electric heat pump. Hybrid desiccant cooling system simulation includes components such as a desiccant rotor, direct and indirect evaporative coolers, heat exchangers, fans, and a heat pump system. Using dynamic simulations by climate conditions, house cooling temperatures and power consumption for both systems are analyzed for 16 days period in the summer season under climate scenarios for the year 2100 prediction. The results reveal that the hybrid desiccant cooling system exhibits a 5-18% reduction in electric consumption compared to the heat pump system.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 추계 학술대회논문집
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• pp.212-218
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• 2003

In order to analyze the heat transfer phenomena in the plasma flames, a mathematical model describing heat and fluid flow in an electric arc has been developed and used to predict heat transfer from the arc to the steel bath in a DC Electric Arc Furnace. The arc model takes the separate contributions to the heat transfer from each involved mechanism into account, i.e. radiation, convection and energy transported by electrons. The finite volume method and a SIMPLE algorithm are used for solving the governing MHD equations, i.e., conservation equations of mass, momentum, and energy together with the equations describing a $\kappa-\epsilon$ model for turbulence. The model predicts heat transfer for different currents and arc lengths. Finally these calculation results can be used as a useful insight into plasma phenomena of the industrial-scale electric arc furnace. From these results, it can be concluded that higher arc current and longer arc length give high heat transfer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 D
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• pp.2310-2312
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• 2004

In Korea Electric Power Corporation (or KEPCO), several Demand-Side Management (or DSM) program have been carried out to effectively meet electric power demand at least costs by modifying customers electricity use patterns. As one of them, KEPCO applies low-priced night thermal-storage power service for heat appliances to facilitate efficient use of power facilities by shifting relatively high daytime demands to night hours to build loads during the off-peak periods. In the market of heat-storage type water-heater, electric water-heater has been mostly used, but it has low energy efficiency and needs high capacity electric equipments. So in order to replace these electric water heaters, 15 HP air-source heat pump water heater is developed in Korea Electric Research Institute (or KEPRI). This paper shows that measurement system for performance testing of heat pump water heater is established and heating capacity and performance is analyzed and measured for out-door environmental change.

• 한국도로학회논문집
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• 제13권1호
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• pp.87-96
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• 2011

대량의 화석연료 소비로 인한 지구 생태계의 부작용에 따라 전 세계적으로 저탄소와 지속가능한 신재생에너지의 활용이 요구되고 있다. 본 논문에서는 여름철 아스팔트 포장도로에서 발생하는 열에너지를 열전현상을 이용하여 전기에너지로 변환하여 에너지 위기를 새로운 성장의 기회로 전환하려 하였다. 이를 위해 열발전소자의 전기적 특성실험과 아스팔트 포장도로 시험체에 열발전소자 매입 및 열 회수 파이프 매입 실험을 통해 에너지 하베스팅 전력을 측정하여 가장 효과적인 아스팔트 포장도로의 열에너지 하베스팅을 위한 시스템 구축방안을 검토하였으며, 결국 아스팔트 포장도로에서 발생하는 지속가능한 열 에너지원을 활용함과 동시에 환경보존과 경제성장을 도모할 수 있는 신개념의 녹색도로 사회기반시설을 제안하였다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.269-272
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• 2008

This paper treats TEGS(Thermo-Electric Generation System) by using two different metals which have N and P types of thermo-electric characteristics respectively. Heat source is the thermal energy from the oxidative reaction of methanol and catalyst. Heat sink is an air cooling system (fan and heat sink). 4 TEMS of $40{\times}40mm$ of TEGS with 500ml methanol produce the electric power of maximum 6W and average 5W for 9 hours.

• 신재생에너지
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• 제19권4호
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• pp.61-71
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• 2023

The necessity of energy utilization using livestock manure has been proposed with the decrease in domestic agricultural land. Livestock manure solid fuel has been investigated as a promising energy resource owing to its convenient storage and use in agricultural and livestock fields. Additional electricity production is possible through the integration of a biomass combustion boiler with the organic Rankine cycle (ORC). In this study, a mathematical system model of the cattle manure solid fuel boiler integrated with the ORC was developed to analyze the components' performance under variable operating conditions. A sensitivity analysis was conducted to confirm the electrical efficiency of the ORC turbine and the applicability of this system. The minimum required waste heat recovery rate was derived considering the system marginal price and levelized cost of electricity of the ORC. The simulation results showed that, in Korea, more than 77.98% of waste heat recovery and utilization in ORC turbines is required to achieve economic feasibility through ORC application.

• KEPCO Journal on Electric Power and Energy
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• 제5권4호
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• pp.365-368
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• 2019