• 열병합발전
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• s.6
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• pp.21-25
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• 1998

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.4 no.1
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• pp.63-66
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• 1975

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2010.04a
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• pp.47-52
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• 2010

• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.107-113
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• 2003

This study was carried out to improve the performance of pre-developed heat recovery devices attached to exhaust-gas flue connected to combustion chamber of greenhouse heating system. Four different units were compared in the aspect of heat recovery performance; A-, B-, and C-types are exactly the same with the old ones reported in previous studies. D-type newly developed in this experiment is mainly different with the old ones in its heat exchange area and tube thickness. But airflow direction(U-turn) and pipe arrangement are similar with previous three types. The results are summarized as follows; 1. System performances in the aspect of heat recovery efficiency were estimated as 42.2% for A-type, 40.6% for B-type, 54.4% for C-type, and 69.2% for D-type. 2. There was not significant improvement of heat recovering efficiency between two different airflow directions inside the heat exchange system. But considering current technical conditions, straight air flow pattern has more advantage than hair-pin How pattern (U-turn f1ow). 3. The main factors influencing on heat recovery efficiency were presumably verified to be the total area of heat exchange surface, the thickness of ail-flow pipes, and the convective heat transfer coefficient influenced by airflow velocity under the conditions of allowable pipe durability and safety. 4. Desirable blower capacity for each type of heat recovery units were significantly different to each other. Therefore, the optimum airflow capacity should be determined by considering in economic aspect of electricity required together with the optimum heat recovery performance of given heat recovery systems.

• Journal of Bio-Environment Control
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• v.9 no.4
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• pp.212-222
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• 2000

This study was performed to investigate the performance of heat recovery device attached to exhaust gas flue connected to combustion chamber of greenhouse heating system. The experimental heat recovery system is mainly consisted of LPG combustion chamber and two heat recovery units; unit-A is attached directly to the exhaust gas flue, and unit-B is connected with unit-A. Heat recovery performance was evaluated by estimating total energy amounts by using enthalpy difference between two measurement points together with mass flow rate of gas and/or air passing through each heat recovery unit depending on 5 different flow rates controlled by voltage meter. The results of this experimental study, such as heat exchange behavior of supply air tubes and exhaust air passages crossing the tubes, pressure drop between inlet and outlet, heat recovery performance of exchange unit, etc., will be used as fundamental data for designing optimum heat recovery device to be used for fuel saving purpose by reducing heat loss amounts mostly wasted outside of greenhouse through flue.

• 열병합발전
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• s.5
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• pp.34-38
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• 1997

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.21-26
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• 2017

In this study, performance tests were conducted to investigate the applicability of a double-tube heat recovery ventilation system. Paper, aluminum, polymer, were investigated as materials for the inner tube using the same exhaust-air volume. In all cases, the temperature exchange efficiency of the aluminum tube was the highest, while the paper tube showed similar results to those of the polymer tube. This probably resulted from the differences in thermal conductivity and thicknesses of the materials. The humidity exchange efficiency was the highest for the paper tubes in all cases, while the aluminum tubes and polymer tubes showed similar results. The total heat exchange efficiency, which includes the values of humidity exchange and temperature exchange, was highest in the case of the paper tube, and the aluminum tube and the polymer tube showed similar results. In the case of the paper tube, sensible heat and latent heat exchange occur at the same time, and the coefficient of energy of the aluminum tube and polymer tube are large values, when to be compared with only applicably sensible heat exchange coefficient of the aluminum tube and the polymer tube of total heat exchange efficiency value. The results of this study could be applied to the design of a ventilation system.

• Journal of the KSME
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• v.35 no.6
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• pp.542-553
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• 1995

복합열병합 발전 플랜트의 장점은 도시 근교에 발전 플랜트를 간단히 건설할 수 있으며, 공해를 크게 줄이면서 독립적인 발전이 가능하다는 측면에서 신도시, 신공업단지, 도서지방 등에서 아주 유리한 것으로 알려져 있다. 또한 가스 터빈 배기열을 이용하여 대규모 주거 지역이나 공업 단 지내에서 필요한 난\ulcorner냉방열이나 공업열원으로의 활용이 손쉬우며, 주변 시설이 복잡하지 않고, 개선된 연소기술에 의하여 공해를 크게 줄일 수 있다. 최근 들어 분당\ulcorner일산\ulcorner부천 지역 등에 열병합 플랜트가 건설되고 있으나 거의 모든 설계기술은 외국 기술에 의존되고 있으며, 국산화 율도 극히 저조하여 '93년도에 완공된 부천 화력(473MW)의 경우 약 30% 정도이다. 복합열병합 발전 시스템은 가스 터빈, 스팀 터빈 등의 터보기계 기술을 근간으로 하며, 열회수장치 및 열교 환장치의 설계기술, 각종 제어기술 등의 종합 설계기술로서 이미 선진국에서는 실용화된지 오 래되었으며 우리 나라에도 여러 종류의 플랜트가 도입되어 사용되고 있다.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.333-339
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• 2000

This study was performed to investigate the performance of heat recovery device attached to exhaust gas funnel connected to combustion chamber of greenhouse heating system. The experiment heat recovery system is mainly consisted of LPG combustion chamber and two heat recovery units; unit-A is attached directly to the exhaust gas funnel, and unit-B is connected with unit-A. Heat recovery performance was evaluated by estimating total energy amount by using enthalpy difference between two measurement points together with mass flow rate of gas and/or air passing through each heat recovery unit depending on 5 different flow rates controlled by voltage meter. The results of this experimental study, such as heat exchange behavior of supply air pipes and exhaust air passages crossing the pipes, pressure drop between inlet and outlet, heat recovery performance of exchange unit, etc., will be used as fundamental data for designing optimum heat recovery device to be used for fuel saving purpose by reducing heat loss amounts mostly wasted outside of greenhouse through funnels.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.10
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• pp.1361-1369
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• 2003

Design performance of hybrid power generation systems, comprised of a gas turbine and an atmospheric pressure molten carbonate fuel cell, has been analyzed. Two different configurations were analyzed and performances were compared. A reference calculation was performed for the design condition of a system under development and simulated results agreed well with the published data. Performances were analyzed in terms of main design parameters including turbine inlet temperature, operating temperature of the fuel cell and pressure ratio. Also examined were the effects of fuel utilization factor and heat exchanger effectiveness. It was found that the relationship between the turbine inlet temperature and the fuel cell temperature should be critically examined to evaluate achievable design performance. Considering current state of the art technologies, a system with the combustor located before the turbine could achieve higher efficiency and specific power than the other system with the combustor located after the turbine.