• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.427-430
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• 2007

Gas turbine disk components have been used by Ni-base superalloys which have high temperature strength for enduring stress induced by high speed rotation. This study introduced the overview of development strategy of precision forging of turbine disk and closed-die forging process for manufacturing good quality gas turbine disk. To make superior quality turbine disk, it is important to select optimal forging process conditions like preform shape, die shape and forging temperature etc. In this paper, closed-die forging process has been studied through the rigid-plastic finite element simulation. Proposed forging process can be used for the successful manufacturing of small-size gas turbine disk.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.136.2-136.2
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• 2011

A dynamic simulation study on SCR process in GTL process was carried out in order to find optimum operation conditions for pilot plant operation. Optimum operating conditions for SCR synthesis gas process were determined by changing operation variables such as feed temperature and pressure. It was also assumed that physical properties of reaction medium were governed by RKS (Redlich-Kwong-Soave) equation. The effect of temperature and pressure on synthesis gas process $H_2$/CO ratio were mainly examined. Dynamic simulation results were fed back to feed operation condition for optimizing productivity, especially for appropriate condition to FT (Fischer-Tropsch) synthesis unit.

• 한국가스학회지
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• 제8권4호
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• pp.15-22
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• 2004

본 연구는 LNG 기지 내 주요 프로세스 설비인 LNG 고압펌프의 운전유량 및 토출압력을 조절함으로서 공정운영 조건을 개선하기 위해 수행되었다. 공정 해석 시뮬레이터인 ASPEN PLUS를 사용한 고압펌프의 실제 운전 성능분석 및 천연가스 송출부하 분석을 통하여 계절별 적정 LNG 고압펌프 토출유량을 결정하였고 그 결과는 현장운전에 적용되었다. 이로 인하여 고압펌프 소모 전력비용을 낮출 수 있으며, LNG기지 내 운영 프로세스 압력을 감소 시켜 보다 안전적인 기지운영을 유도할 수 있었다.

• 한국산업융합학회 논문집
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• 제21권6호
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• pp.429-437
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• 2018

The process gas piping of the offshore plant can cause a massive explosion if the gas leakage occurs during operation. For the purpose of precaution of gas leakage accident, an air pressure test is performed on the process equipment tests using a test pump as much as the power to the piping inner side, mix 99% nitrogen gas and 1% helium gas. The purpose of the air pressure test is to check the work conformity process by handling and regulation for initial piping process, assembly, installation of module, welding, center alignment of the pipes assembling flange gasket in an unrestrained free state. In this paper, the regulation of the problematic air pressure test was analyzed and the solution criteria were established. And leakage tests of existing equipment were performed applying these solution methods. As a result, it was confirmed that there was no problem.

• 한국가스학회지
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• 제14권4호
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• pp.51-55
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• 2010

전 세계적으로 온실가스인 이산화탄소 배출을 감축하기 위하여 다양한 노력이 이루어지고 있다. 이러한 상황에서 이산화탄소가 함유된 중소규모 가스전은 LNG로 개발하기에는 경제성이 떨어진다. 특히 가스전에 포함된 이산화탄소를 분리하기 위하여 분리설비가 추가로 설치되어야 한다. 따라서 플랜트 건설비용이 증가하고, 분리된 이산화탄소는 대기중으로 배출되어 온실가스 감축과는 상반되는 결과를 가져온다. 이러한 비경제적인 가스전에 KOGAS DME Process를 적용하면 가스전에 포함된 이산화탄소를 천연가스와 함께 원료가스로 활용할 수 있어 경제성이 높아진다. KOGAS DME Process는 합성가스를 제조하는 Tri-reformer(삼중개질반응기)를 통하여 $H_2$와 CO로 이루어지는 합성가스를 제조하는데 원료가스로 천연가스와 산소, 스팀, 이산화탄소를 활용한다. 여기서 사용되는 이산화탄소는 공정상 발생하는 이산화탄소를 회수하여 원료가스로 활용하게 된다. 따라서 본 연구에서는 공정상 발생하는 이산화탄소의 발생량과 원료가스로 사용되는 이산화탄소의 사용량 그리고 가스전에 포함된 이산화탄소의 함량을 분석하여 가스전에 포함된 이산화탄소의 활용범위를 연구하고자 한다.

• 한국가스학회지
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• 제15권1호
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• pp.1-8
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• 2011

최근 석유 위주의 에너지원에서 가스나 신재생에너지와 같은 새로운 에너지원을 생산 혹은 이용하는 공정들에 대한 연구가 활발한 가운데 이러한 공정들의 상업화를 위해서는 조업 중 에너지 절감과 생산 단가의 경제성 확보가 필수적이며, 이를 위해서는 적합한 공정제어 기법의 도입이 필수적이라 할 수 있다. 본 논문에서는 지난 50여 년간 공정산업에 적용된 다양한 공정제어 기법 중 큰 기틀이 되는 몇몇 기술을 소개하고, 가스 관련 공정의 응용 예 및 앞으로 나아갈 방향에 대해 논하였다.

• 한국기계가공학회지
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• 제19권4호
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• pp.36-44
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• 2020

This study analyzed the deformation behavior of the high density polyethylene (HDPE) bottle in the blow molding process. We carried out finite element (FE) simulations using ANSYS Polyflow. First, the axisymmetric model was executed by 2D FE-simulation to determine the change of bottle wall thickness during the molding process. Then, the square model of the bottle was executed by 3D FE-simulation to gauge the effects of gas pressure on the change of wall thickness. The experiment results showed that the FE-simulations were able to upgrade the quality of the HDPE bottle in the blow molding process. These results can be used as guidance in adjusting gas pressure, as well as be extended for further study to determine process parameters such as temperatures, forming velocity, parison shape, etc.

• 한국가스학회지
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• 제7권3호
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• pp.7-12
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• 2003

[ $CO_2$ ]와 $H_2S$ 각각 1.37, 1.70 몰$\%$를 포함하고 있는 산성의 천연가스를 sweetening하고자한다. 본 연구에서는 천연가스 하부에서 100 MMSCFD 안에 산 가스의 농도가 5 ppm이 되도록 amine 처리능력을 디자인하는 것이다. 천연가스에 포함된 $CO_2,\;H_2S,\;H_2O$와 amino 성분들의 K-값은 Kent-Eisenberg model를 사용하였다. Ball과 Veldman이 새롭게 디자인한 gas sweetening 공정을 상응 정상상태 모사기를 이용하여 모델링한 후 최적화하였다. 모사 결과는 현재 운전하고 있는 공정보다 더 많은 경제적인 개선을 이끌 것이다.

• International Journal of Air-Conditioning and Refrigeration
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• 제6권
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• pp.56-66
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• 1998

The absorption process of water vapor in a liquid film is an important process in LiBr-Water absorption system. The composition of the gas phase, in which a non-absorbable gas is combined with the absorbate, influences the transport characteristics. In the present work, the absorption processes of water vapor into aqueous solutions of lithium bromide in the presence of non-absorbable gas are investigated. The continuity, momentum, energy and diffusion equations for the solution film and gas are formulated in integral forms and solved numerically. It is found that the mass transfer resistance in gas phase increases with the concentration of non-absorbable gas. However the primary resistance to mass transfer is in the liquid phase. As the concentration of non-absorbable gas in the absorbate increases, the interfacial temperature and concentration of absorbate in solution decrease, which results in the reduction of absorption rate. The reduction of mass transfer rate is found to be significant for the addition of a small amount of non-absorbable gas to the pure vapor, especially at the outlet of tube where the non-absorbable gas accumulates. At higher non-absorbable gas concentration, the decrease of absorption rate seems to be linear to the concentration of non-absorbable gas.

• Nuclear Engineering and Technology
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• 제36권4호
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• pp.338-345
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• 2004

This study examines the sensitivity of several fabrication parameters for dry process fuel, using a random sampling technique. The in-pile performance of dry process fuel with irradiation was calculated by a modified ELESTRES code, which is the CANDU fuel performance code system. The performance of the fuel rod was then analyzed using a Monte Carlo simulation to obtain the uncertainty of the major outputs, such as the fuel centerline temperature, the fission gas pressure, and the plastic strain. It was proved by statistical analysis that for both the dry process fuel and the $UO_2$ fuel, pellet density is one of the most sensitive parameters, but as for the fission gas pressure, the density of the $UO_2$ fuel exhibits insensitive behavior compared to that of the dry process fuel. The grain size of the dry process fuel is insensitive to the fission gas pressure, while the grain size of the $UO_2$ fuel is correlative to the fission gas pressure. From the calculation with a typical CANDU reactor power envelop, the centerline temperature, fission gas pressure, and plastic strain of the dry process fuel are higher than those of the $UO_2$ fuel.