• 한국연소학회:학술대회논문집
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• 2005.10a
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• pp.148-155
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• 2005

In this study, Development of 300,000kcal/hr high velocity Injection burner with fuel multi-stage was performed using experiments. The characteristics of NOx emission in multi fuel/air staged combustor have been experimentally studied. The design concept of multi fuel/air staged combustor is creation of two separate flame, a primary flame is largest access air combustion and the secondary flame is complete combustion zone, where most of fuel bums. Experiments were performed on an industrial scale in a laboratory furnace and Liquefied Natural Gas(LNG) was used as primary and secondary fuels. Comparison of outlet NOx and outlet Temperature under various air rate and primary/ secondary fuel ratio was performed. The test demonstrated that NOx emission con be reduced by 70% in accordance with operating conditions.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.77-80
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• 2005

This paper presents a theoretical and experimental study on the damage identification of structures. In civil and aerospace, significant work has been done in the area of detecting damage in structures by using changes in the dynamic response of the structure. In this paper a method based on the changes in the strain energy of the structure will be discussed. To evaluate the effectiveness of the method it will be applied to both beam and LNG(liquefied natural gas) carrier.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.4
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• pp.543-550
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• 1998

From the power plant in a steel plant, environment pollutants such as $SO_x$, $NO_x$, CO and $CO_2$ are emitted by combustion reactions of the fuels which are by-product gases, oil and liquefied natural gas(LNG). To reduce the amounts of the pollutants, it is important to build a predictive model for the emission of the pollutants. In this paper, model that predict the amounts of generated pollutants for the used fuel is developed by using Gibbs free energy minimization method[1] with the temperature correction technique. For some data set, the calculation results from this model are compared with the real emission amounts of $SO_x$, $NO_x$, and the result of the calculation by both ASPEN PLUS which is a commercial simulation software. This model shows good results and can be applied to other power plants.

• Journal of the KSME
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• v.29 no.6
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• pp.627-635
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• 1989

최근 여러 선진국 등에서 도시환경 보존을 위하여 천연가스 차량에 대한 관심이 고조되어 대부분 천연가스와 기존연료 검용차량을 개발하여 계속 시험 중에 있으며, 천연가스 전용 차량으로서는 미국의 포드사가 1984년에 AFV (alternative fuel vehicle)를 개발하였고 일본의 스즈끼 공업이 1988년 LNG(liquified natural gas) 전용 차량을 개발하여 실용화를 추진하고 있다. 천연가스연 료는 청정에너지라는 장점에 저렴한 가격, 풍부한 매장량, 기존 가솔린이나 디젤엔진 보다 4배 정도 긴 엔진 수명연장, 충돌시 푹발위험에 대한 안전성 등의 장점에도 불구하고 연료통의 큰 부피로 인한 단거리 운행 가능과 충분한 가스충진소 설치 문제 등의 단점이 있으나 최근 기술의 발전속도로 볼 때 이러한 문제점은 조만간에 해결될 것이며 자동차용으로 천연가스의 이용은 세계적으로 확실될 것이라 판단된다. 이러한 세계적인 추세에 따라 국내에서도 냉난방용으로 전기모터 대신 천연가스 엔진구동을 위해 개발에 착수하였으며 단계적으로 자동차용 천연가스 엔진개발을 계획하고 있다.

• Transactions of The Korea Fluid Power Systems Society
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• v.3 no.4
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• pp.8-13
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• 2006

The high pressure cryogenic ball valve is used to transfer the liquefied natural gas which temperature is $-196^{\circ}C$, supplied pressure is $168kgf/cm^2$. In the present work, the temperature distribution and thermal deformation is calculated numerically. The CAR and CFD methods are useful to predict the thermal matter and the inner flow field of high pressure cryogenic ball valve. For this reason, to optimum design of the cryogenic ball valve, the theological behavior of the supplied LNG in a cryogenic valve has been studied. The governing equations are discredited and solved numerically by the finite-volume method and finite-element method. In this study, we designed the high pressure cryogenic ball valve that accomplishes zero leakage by elastic seal at normal temperature and metal seal at high temperature.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.189-192
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• 2004

Test Facility for hot firing test of small size liquid rocket engine has been developed to research the cooing characteristics of kerosene for cylinder part especially. Propellants for the tests are kerosene and liquid oxygen as fuel and oxidizer respectively and they are fed by gaseous nitrogen. The engine components used hot firing test except for cylinder are cooled by tap-water. Valves for supply of propellants and coolants are controlled by pneumatically. System control and data recording are conducted automatically.

• Geosystem Engineering
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• v.21 no.6
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• pp.309-317
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• 2018

We employ a three-dimensional indirect boundary element method (BEM) to simulate temperature change around an underground liquefied natural gas storage cavern. The indirect BEM (IBEM) uses fictitious heat source strength on boundary elements as basic variables which are solved from equations of boundary conditions and then used to compute the temperature change at other points in the considered problem domain. The IBEM requires evaluation of singular integration for temperature change due to heat conduction from a constant heat source on a planar (triangular) region. The singularity can be eliminated by a semi-analytical integration scheme. However, it is found that the semi-analytical integration scheme yields sharp temperature gradient for points close to vertices of triangle. This affects the accuracy of heat flux, if they are evaluated by finite difference method at these points. This difficulty can be overcome by a combination of using a direct numerical integration for these points and the semi-analytical scheme for other points distance away from the vertices. The IBEM and the hybrid integration scheme have been verified with an analytic solution and then used to the application of the underground storage.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.919-920
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• 2009

액화 천연 가스 플랜트 시뮬레이터는 막대한 자본 투자가 필요한 대형 시스템 설계 및 건설 단계에서 사전에 설계 오류 검출 및 시스템 검증을 함으로써 많은 비용을 절약해줄 수 있는 중요한 시스템이다. 이 연구에서는 플랜트, 시뮬레이터, 운전원 훈련 시스템 및 제어시스템을 운전하는 과정에서 발생하는 정보를 효과적으로 처리하기 위해서 구축되는 정보 처리 시스템의 기본 설계에 관한 내용을 소개한다. 전체 시스템은 물리적 플랜트와 가상 플랜트로 나눌 수 있고 가상 플랜트는 시뮬레이터와 운전원 훈련 시스템으로 구현되며, 제어 시스템은 PLC로 구현하고 Modubus 프로토콜과 OPC 서버를 통해 데이터 처리가 가능하다. 플랜트로부터 생성되는 데이터 처리에서는 실시간 데이터 처리 속도가 중요하므로 실시간 데이터베이스를 도입하였다. 실제 플랜트 데이터와 시뮬레이터 데이터는 상호 교환이 가능하도록 구성하였다. 본 시스템 설계는 기본 설계 단계이므로 향후 LNG 플랜트에 적용하기 위해서는 상세 설계가 필요하다.

• Journal of Mechanical Science and Technology
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• v.20 no.4
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• pp.545-553
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• 2006

Generally, the temperature drop under $0^{\circ}C$ on vaporizer surface creates frozen dews. This problem seems to increase as the time progress and humidity rises. In addition, the frozen dews create frost deposition. Consequently, heat transfer on vaporizer decreases because frost deposition causes adiabatic condition. Therefore, it is very important to solve this problem. This paper aims to study of the optimum design of used vaporizer at local LNG station. In this paper, experimental results were compared with numerical results. Geometries of numerical and experimental vaporizers were identical. Studied parameters of vaporizer are angle between two fins $(\Phi)$ and fin thickness $(TH_F)$. Numerical analysis results were presented through the correlations between the ice layer thickness $(TH_{ICE})$ on the vaporizer surface to the temperature distribution of inside vaporizer $(T_{IN})$, fin thickness $(TH_F)$, and angle between two fins $(\Phi)$. Numerical result shows good agreement with experimental outcome. Finally, the correlations for optimum design of vaporizer are proposed on this paper.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.255-258
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• 2002

Liquid rocket engines using liquefied natural gas (LNG) or methane as a fuel is known to have several good characteristics, such as high specific impulse compared to other hydrocarbon fuels, environment-friendly exhaust gas, low production cost, and re-usability with low soot generation in the cooling channel. In this study, experimental combustion chambers capable of using LNC and $CH_{4}$ are being researched through experimental firing tests, and within easy range of eyes' inspection, there are the periodical existence of soot or discoloration in the chamber wall surface. This result means that mixture ratio of oxidizer and fuel fluctuates periodically between outer-row injectors in the mixing head in the circumferential direction. Therefore, based on this phenomenon, the variation of mixture ratio near the chamber wall caused by the spill pattern of a shear coaxial injector was analyzed quantitatively and the thermal heat flux Into the cooling channel is modified. Then, the calculated and modified results are compared with the measured ones.