• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.12
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• pp.1255-1265
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• 2001

A numerical study has been conducted to characterize the transient flow in a utility gas turbine burning natural gas. The solution domain encompasses the supply gas pressure regulator to the combustor of the gas turbine that employs multi-nozzle fuel injectors. Some results produced for verification in the present study agree suite well with the experimental ones. It is found that the total gas flow may decrease noticeably during its combustion mode change, which would be the reason of momentary combustion upset, when a reference case of opening ratios of control valves in the system is applied. Several parameters are then varied in order to make the total gas flow stable over that period of time. Results of this study may be useful to understand the unsteady behavior of combustion system burning natural gas.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.2
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• pp.146-153
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• 2013

CNG buses has contributed to improve air quality in cities. But it is difficult to meet the next emission regulations such as EURO-VI without the help of additional post-processing device. Hydorgen has higher flame speed and lower combustion temperature that make it thermal efficiency increase with leaner operation. Using hydrogen natural gas blend (HCNG) fuel is promising technology which can reduce $NO_x$ and $CO_2$ emissions for a natural gas vehicle. However, fuel flow rate of HCNG should be increased since hydrogen's energy density per volume is much smaller than natural gas. In the present study, the characteristics of fuel supply system and its applicability were evaluated in a heavy duty natural gas engine. The results showed that the potential of fuel pressure regulator and fuel metering valve had enough capacity with HCNG. Employed mixer did not affect the distribution characteristics of mixture.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.565-567
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• 2008

가스터빈용 자동전압조정기는 발전기 출력 전압을 측정하여 발전기 단자 전압과 계자 전류를 제어하며, 발전기 여자시스템 보호/제한 기능을 수행한다. 본 논문에서는 전력연구원이 개발한 가스터빈 자동전압조정기의 시작품에 대한 소프트웨어와 하드웨어에 설계 및 제주화력 가스터빈에 현장 적용한 결과를 상세히 기술하였다.

• Journal of the Korean Institute of Gas
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• v.12 no.2
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• pp.105-109
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• 2008

A safety valve has a valve mechanism for the automatic release of gas from piping system when the pressure exceeds preset limit cause of a defect of a pressure regulator, condensation of water in a pipe. Therefore, for the safety of pressure regulating station, it is essential to study the flow regime and characteristics of safety valve. This article presents the numerical analysis on the flow analysis, the ejection capacity and required effective discharge area of the safety valve that is established in pressure regulating station. Then, the results are compared and analyzed with domestic and foreign regulations such as API(America Petroleum Institute), EN(European Standard), and NF(Norme Francise). Moreover, the installation number of safety valve is considered by using domestic and foreign regulations and maximum reguired effective discharge area of safety valve.

• The Transactions of the Korean Institute of Power Electronics
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• v.13 no.6
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• pp.411-419
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• 2008

SFC(Static Frequence Converter)system has come to be used as start up drive system for large synchronous motor in many industry applications. Many papers have been presented the control algorithm for pumped storage power generation using SFC system but they did not included about start up algorithm of SFC system for gas turbine. This paper presents the field weakening control algorithm for a large synchronous motor using output signal of anti-windup in PI current regulator and the results of experiment show that the proposed algorithm is proper and effective.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1317-1321
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• 2009

Natural gas liquefaction plant and LNG carrier needs large capital investment. Therefore a lot of small or middle scale natural gas fields aren't developed due to poor profitability. If natural gas is made to gas hydrate instead of liquefaction, developing small-scale natural gas field can be profitable because building cost of gas hydrate plant and carrier are economical. Because the process of making gas hydrate consumes much energy, the gas hydrate formation process has to be optimized for energy consumption. In this study, gas hydrate formation process was investigated experimentally. Experimental apparatus consists of reactor, pressure regulator, chiller, and magnetic stirrer. 99.95% methane was used to make gas hydrate. Tests were conducted at variable pressure and temperature condition.

• Journal of the Korean Institute of Gas
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• v.9 no.2 s.27
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• pp.38-42
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• 2005

This study introduced concept of safety valve about development of valve for LP gas cylinders. LP gas cylinders are used more because of convenience of use, but a lot of accidents are occurred. Specially, it is used by purpose to injure glossary or others and is sometimes used to a demonstration tool. Korean government was making mandatory to use overuse cutoff valve to reduce accident, but it is real condition that product development is not following. In this study, introduce concept of safety valve that introduce more original safety concept than overuse cutoff valve. This was developed by method that insert module to present use valve and flowing of gas is controlled in state that hose or regulator un-connects to valve. Also, flowing of gas cut-off immediately if hose is cut or occurrence of overuse is produced even if is using normally.

• Proceedings of the ESK Conference
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• 1997.10a
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• pp.214-219
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• 1997

In spite of many accidents still occur repeatedly. The reason why we have so many accidents in industrial plants is mainly due to lack of effective safety education. Most safety education committed by safety staff is composed of general education and/or accident case studies. However, it is quite natural that the safety education should be more task- specific rather than general, if it be effective. Thus for preventing gas leakage accidents during changing explosive gas cylinders, this study aimed to analyze a manual chaning work in semiconductor plants, and to deaw importamt educational points. With the help of HRA and ETA, the most important task truned out to be reconfirmation of regulator gauges. Under the assump- tion of independent events, the estimated leakage probability was 23004E-05 which seriously understimated the probability, 8.1008E-05 under the assumption of dependent events. And the most probable situation would be gas leakge from the used gas cylinder. It was made clear that the assumption of independence could distrot safety educational focus.

• Journal of the Korean Institute of Gas
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• v.23 no.6
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• pp.61-66
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• 2019

Unlike NG supplied through pipes, LPG is mainly used for independent storage of cylinders or small storage tanks. As LPG is widely used in islands and underdeveloped areas, accidents due to neglect of safety management are high. Houses and businesses that have LPG accidents are likely to be damaged due to relatively high population density. Therefore, the necessity of strengthening the safety management of LPG is constantly raised. Accordingly, in 1996, Korea Gas Safety Corporation conducted an LPG leak test. In this study, based on the 96-year experiment, the gas leakage measurement of LPG vessels was conducted by adding several conditions such as outside temperature and pipe condition. Through this, the trend of leakage for various scenarios of LPG leakage was examined. In the case of a gas leak, when the article which may affect the pressure such as a regulator is not connected, the leakage amount is greatly changed by the outside air temperature, and when the regulator is fastened, the influence of the outlet pressure is large. It is expected that the experiment can be used as basic data for determining gas accidents and leakages that may occur later.

• Journal of Korean Institute of Fire Investigation
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• v.11 no.1
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• pp.1-8
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• 2008

The purpose of this paper is to report gas fire accident based on classification of the major gas fire causes (including handling mistakes, inferior goods, etc.), fire classifications (fire, explosion, leakages, etc.), damage levels(1st, 2nd, 3rd, 4th grade levels), casualties (death, serious wound, slight injury) since gas fire has been generated according to growth of gaseous fuel consumption on home and enterprises with various accident causes. Among gaseous fuels, LPG facility can be c1assified as gas container, pressure regulator, gas hose, interim valve, combustion port. Any fire or any explosion can be caused from handling mistakes, inferior goods on each parts as stated above. Exact gas fire causes shall be identified based on previous case studies on similar fires with consideration of lesson learns.