• Journal of Korea Foundry Society
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• v.43 no.6
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• pp.271-278
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• 2023

In the present study, A356 melt degassing experiments were conducted under various impeller rotation speed and inert gas flow rate conditions to determine changes in the melt temperature, composition and density during a degassing treatment. The melt temperature was found to decrease gradually as the degassing time increased, but a clear correlation between the impeller rotation speed or inert gas flow rate and the melt heat loss could not be confirmed. Regardless of the impeller rotation speed or inert gas flow rate, the Mg and Ti contents in the A356 melt scarcely changed, even after degassing for more than 10 minutes, while Sr contents decreased at the maximum degassing rate of 70 ppm. From a quantitative analysis of the degassing rate under each experimental condition based on the hydrogen concentration in the melt derived from the melt density and the degassing model equation, the inert gas flow rate was found to affect the degassing rate rather than the impeller rotation speed under the degassing operation condition employed in the present study.

• Resources Recycling
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• v.7 no.3
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• pp.42-51
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• 1998

Hydrogen in atmosphere can easily dissolve in melt of light metal alloys. Increasing demand for recycling of light metal a alloys has, therefore, focused attention on the removal of hydrogen gas, and alloy addition in melt has become an imporLant r refining process. For this purpose behaviors of mixing and hydrogen degassing in impeller agitated refming vessel with/without barnes were investigated. Flow patterns, mixing time behavior and kinetics of degassing in various agitating conditions were analysed in watet model experiments. And, numerical analysis on turbulent flow pattern in impeller agitated vessels was performed.

• 기계와재료
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• v.10 no.1 s.35
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• pp.101-113
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• 1998

• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.81-90
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• 2004

This paper describes the results of combustion performance test of fuel-rich gas generator(GG) using LOx and kerosene as propellant at off-design conditions. The chamber pressure is thought to be a function of O/F ratio and total propellant mass flow rate. The test shows that the spatial temperature deviation at the exit of gas generator remains within 7.5K and that the average gas temperature at the exit is a function of propellant O/F ratio. The results of firing test of gas generator at off-design conditions, especially the relation between gas temperature and O/F ratio, can provide useful data for the design of future gas generator and for the development of low-O/F ratio reaction analysis code.

• Nuclear industry
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• v.37 no.7
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• pp.40-53
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• 2017

에너지경제연구원은 6월 20일, 정부의 전원구성안의 영향을 발전 비용, 온실가스, LNG 수요, 전력수급, 물가 및 GDP 차원에서 다각적으로 분석한 보고서를 발표했다. 보고서는 2016년에 탈원전-탈석탄 공약과 같이 원전과 석탄 비중이 대폭 줄어들고 신재생에너지 발전량 비중이 20%로 확대된다고 가정하고 발전 비용, 온실가스, LNG 수요, 전력 수급 영향 등을 2016년 실적치와 비교하였으며, 2029년 기준 제7차 전력수급기본계획(7차 계획) 대비 탈원전-탈석탄 시나리오에 미치는 영향을 제시했다. 보고서 전문을 게재한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4713-4716
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• 2014

Several methods that have been used to manage a degasing process in recent years, such as an injection method that uses aluminum molten metal powder and chemicals, and the input method that supplies argon and nitrogen, or chlorine gas using a gas blow-tube. On the other hand, these methods have some problems, and it is a difficult process to handle pollution due to the production of considerable toxic gases, such as chlorine and fluoride gas, irregular effects, and lowering work efficiency due to the excessive processing time. The problems that are most fatal are the production of considerable sludge due to a reaction of aluminum molten metal with chemicals, loss of metals, and the decreasing life of refractory materials. To solve these problems, this study developed a technology that is related to continuous casting of molten aluminum metal and monolithic degasing apparatus.

• Proceedings of the Optical Society of Korea Conference
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• 1990.02a
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• pp.3-8
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• 1990

방전여기 방식의 KrF 엑사이머 레이저의 컴퓨터 시뮬레이션 프로그램을 개발하여 방전중의 KrF 형성, 탈여기 및 흡수채널에서 완충가스의 영향을 이론적으로 해석하였다. 생성효율은 Ne 완충가스에서 He보다 2.2배 정도 높았으며, KrF의 탈여기는 He과 Ne 완충가스에서 각각 50%, 30% 정도의 비율을 차지하였다. 그러나 흡수 과정에서는 완충가스의 영향이 크지 않은 것을 알 수 있었다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.851-852
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• 2012

• Journal of Korea Foundry Society
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• v.30 no.2
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• pp.55-59
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• 2010

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1997.10a
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• pp.99-104
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• 1997

기존의 천연가스 가스터빈 시스템을 IGCC 발전소에 적용함에 있어 야기되는 탈설계점효과를 고려할 수 있는 압축기 성능곡선의 예측방법을 제안하였다. 압축기 성능해석방법으로는 익렬요소방법에 전압력손실, 유동편차각 모델들을 결합하여 사용하였으며, 본 방법에 의한 예측결과와 실제 압축기 성능실험결과를 비교하였다. 예측결과가 다양한 압축기 운전조건에 대해 시험결과와 비교적 잘 일치하였으며, 이를 통해 본 예측방법이 IGCC 공정설계 및 성능평가시 가스터빈 탈설계점 효과를 분석할 수 있는 기본 모듈로 사용될 수 있을 것이다.