• 한국수소및신에너지학회논문집
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• 제30권5호
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• pp.395-400
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• 2019

Comparative studies between single- and two-stage refrigeration cycle using propane as a refrigerant have been performed for a vapor recompression refrigeration cycle. PRO/II with PROVISION release 10.2 from AVEVA company was used, and the Soave-Redlich-Kwong equation of state model with Twu's alpha function was selected for the modeling and optimization of the refrigeration cycle for the reliquefaction of BOG coming out from the LPG storage tank. In two-stage refrigeraton cycle, 24.8% of compressor power was reduced compared to that of single-stage refrigeration cycle through the optimization works.

• 한국안전학회지
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• 제15권2호
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• pp.59-62
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• 2000

Almost accidents related with gas have started with the leakage of LPG(Liquefied Petroleum Gas) in the open air. But experimental data of LPG leak jet are difficult to find because the safety of experiment is hard to secure and its phenomenon is not steady but transitional. This study is focused on the phenomena of injection jet of liquid butane to the open air. Simple experiment shows that only liquid butane jet in the open air is possible due to the slow vaporization because of low temperature difference between the liquid and air and low vapor pressure of liquid butane. Comparing with the water, 25~40% more liquid butane flow through the tube under the same pressure difference driving.

• 한국가스학회지
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• 제25권4호
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• pp.49-56
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• 2021

액화석유가스(Liquefied Petroleum Gas)는 Propane(C₃H₈)과 Butane(C₄H₁₀)을 주성분으로 한 가스를 액화한 것으로 구분된다. LPG는 혼합 성분에 따라 품질의 차이가 커 성분 함량을 정확하게 측정하는 것이 중요하다. 이와 같은 물질은 혼합물의 성분별로 상온에서는 액체와 기체가 같이 공존해 정확한 측정이 까다롭다. 따라서 탄화수소의 성분별 농도의 측정 불확도가 높아 실제 함량 기준과 많은 차이가 발생하는 문제점을 안고 있다. 그러므로 탄화수소 물질의 조성과 정확한 농도 측정을 위해 혼합 액체 프로판 표준가스의 개발이 필요하였다. 혼합 액체 프로판 표준가스는 ISO-6142(2015)의 중량법으로 벨로즈형 정압실린더에 제조되었다. 제조한 4병의 표준가스에서 균질성이 GC-FID로 확인되었다. 제조 상대확장불확도는 0.01 % - 0.30 %, 균질성은 0.03 % - 0.25 %이었다. 이 혼합 액체 프로판 표준가스에서 중량법, 제조 일치성, 실린더 흡착 여부 및 장기 안정성에 대한 상대확장불확도는 0.26 % - 1.39 %(신뢰도 약 95 %, k=2)이내로 개발되었다.

• 에너지공학
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• 제15권1호
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• pp.23-27
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• 2006

가정용 LPG(Liquefied petroleum gas)저압조정기의 성능 및 수명평가를 위하여, 저압조정기의 사용경과에 대한 안전장치의 성능, 조정압력 및 폐쇄압력, 조정 스프링 및 다이어프램의 기계적 물성을 분석하였다. 실험결과, 사용시간의 경과에 따른 조정성능 및 물성저하가 관찰되었으며, 사용기간 6년 이상의 조정기는 성능 저하가 매우 심각한 것으로 분석되었다.

• 한국안전학회지
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• 제11권2호
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• pp.67-78
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• 1996

Gas sensing element, $\gamma-Fe_2O_3$was synthesized by dehydration, reduction, and oxidation of $$${\gamma}$-FeOOH, which was synthesized with $FeSO_4\;{\cdot}\;7H_2O$ and NaOH. They were produced as a bulk-type, a thick film-type. Then, their responses and mechanisms of response to the gas of liquefied-petroleum were studied. The qualities of gas sensing elements are decided by the structure and the relative surface area. In the process of $\alpha-FeOOH $synthesis, the effects of reaction conditions as the equivalent ratio, on the structure and the relative surface area of gas sensing element were observed. The changes of the structure were measured with XRD, SEM, TG-DTA and BET. The resistance changes of the synthesized gas sensor in the air were measured. The response ratio were also measured for the changes of working temperature and gas concentration. As a result of analysis with XRD, it was confirmed that the the best conditions for the synthesis of $\alpha -FeOOH$ were equivalent ratio 0.65. The thick film-type element of $\gamma-Fe_2O_3$responded more quickly than the bulk-type did. The structure and the relative surface area of the $\alpha-FeOOH $were confirmed as the important factors deciding gas response charcteristics.

• 한국가스학회지
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• 제10권1호
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• pp.26-31
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• 2006

LPG충전시설에 설치된 각종 안전장치의 유효성을 평가하기 위해 하역작업 중 탱크로리의 비등액체팽창증기폭발(BLEVE, Boiling Liquid Expanding Vapor Explosion) 시나리오에 대해 빈도분석을 수행하였으며, 분석방법으로는 정량적인 분석법인 결함수목분석(Fault Tree Analysis)법을 사용하였다. 안전장치의 유효성은 안전장치의 부착여부와 용량변화에 따른 빈도변화를 관찰함으로써 간접적으로 평가하였다. 이 분석을 통해 허용 가능한 위험수준을 만족하기 위해 필수적인 안전장치와 설치 우선순위를 도출할 수 있었다.

• 유공압시스템학회논문집
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• 제2권3호
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• pp.6-11
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• 2005

A household gas valve is used for flow control of LPG(Liquefied Petroleum Gas) or LNG(Liquefied Natural Gas) of which pressure is about $200mmH_2O(\fallingdotseq\;0.0196[bar])$. Currently, two kinds of valves such as rotary type and button type are widely used in many applications. But, these valves have some problems that they are not controllable and reliable. Piezo actuation combined with modem microelectronics provides a reliable, quiet, low energy, infinitely adjustable gas valve. In this paper, gas valve using piezo actuator which are bimorph and a circle type was studied. Also, Prototype for gas valve was manufactured and characteristics of the prototype gas valve were analyzed.

• Korean Chemical Engineering Research
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• 제50권2호
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• pp.353-357
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• 2012

액화석유가스(liquefied petroleum gas, LPG)에 디메틸에테르(dimethyl ether, DME)가 첨가된 DME-LPG 혼합연료의 탄화수소 화합물을 가스크로마토그래피(GC)를 이용하여 정성 정량분석하는 새로운 분석방법을 연구하였다. DME-LPG 혼합연료는 함산소화합물(oxygen-containing compound)인 극성의 DME와 비극성물질인 LPG로 구성되어 있기때문에 하나의 GC 컬럼에서 모든 성분을 완전히 분리하기가 어렵다. 따라서 서로 다른 성질의 화합물이나 아주 복잡한 화합물 중 목표물질의 분석에 응용되고 있는 Deans switching 시스템을 도입하였다. 상기 시스템은 두 개의 GC 컬럼 사이에 유체의 압력 제어를 통하여 용출되는 물질의 흐름 방향을 변경시켜주는 기술로서, 이 방법을 이용하여 DME와 LPG를 서로 다른 컬럼에서 분리하여 한번의 시료 주입으로 DME-LPG 혼합연료의 모든 탄화수소 화합물을 정성 정량분석할 수 있었다. 또한 DME 합성과정에서 부산물로 생성될 수 있는 메탄올, 포름산메틸, 에틸메틸에테르 같은 미량성분까지 분석이 가능하였다.

• 대한기계학회논문집B
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• 제28권10호
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• pp.1178-1183
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• 2004

The purpose of this study was to investigate the influence of compression ratio on engine performance in a LPG(Liquefied Petroleum Gas) engine converted from a diesel engine. In ordor to determine the ideal compression ratio, a variable compression ratio 4-cylinder engine was developed. Retrofitting a diesel engine into a LPG engine is technically very complicated compared to a gasoline to LPG conversion. The cylinder head and the piston crown were modified to bum LPG in the engine. Compression ratios were increased from 8 to 10 in an increment of 0.5, the ignition timing was controlled to be at MBT(Minimum Spark Advance for Best Torque) for each case.

• International Journal of Automotive Technology
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• 제6권3호
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• pp.215-219
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• 2005

Liquefied petroleum gas (LPG) has been used as motor fuel due to its low emissions and low cost. A liquid direct injection system into a cylinder was suggested as a next generation system to maximize a fuel economy as well as a power. This study addresses the analysis of the LPG spray injecting from single hole injector. Two different test conditions are given, which are a fully developed spray case with various injection pressures and a developing spray case with ambient pressure variation. The LPG spray photographs are compared with the sprays of gasoline and diesel fuel at the same conditions, and the spray angles and penetration lengths are also compared, and then the spray behavior is analyzed. The LPG spray photos show that the dispersion characteristic depends very sensitively on the ambient pressure soon after injection. The spray angle is very wide in a low ambient pressure condition until the saturated pressure, but the angle is quickly reduced at the condition over the pressure. However, the down stream of the LPG spray shows much wider dispersion and less penetration than those of gasoline and diesel sprays regardless ambient pressure condition.