• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.214-215
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• 2000

1960년대 이래로 산업과 교통수단의 발달은 지역적 환경 오염을 야기시켰지만, 대량의 화석연료 및 합성화학물질의 사용은 대기와 물을 매개로 전지구적 규모의 오염형태로 진행되어 가고 있다(Simonich and Mites, 1995). 이러한 추세와 함께 환경 중 존재하는 다이옥신을 비롯한 내분비계장애물질의 오염은 극미량 존재하에도 강한 독성을 나타내므로 생태계에 끼치는 영향은 큰 것으로 보고되고 있다. (중략)

• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.4
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• pp.44-51
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• 2017

An experimental results on the dynamic characteristics of hydrocarbon/air premixed flames with ultrasonic standing waves are presented and compared. Images of the propagating flames were acquired by using a high-speed camera, and the flame behavior of methane/air and propane/air premixed flame were closely scrutinized through the image post-processing. At the fuel-lean conditions, the flame propagation velocity increased due to the intervention of the ultrasonic standing wave and vice versa at the fuel-rich conditions.

• Journal of the korean Society of Automotive Engineers
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• v.18 no.6
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• pp.33-39
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• 1996

최근 서울의 일부 지역에서는 오존 주의보에 의한 대기 오염의 수치가 발표되고 있어 이의 심각성이 대두되고 있다. 대기오염의 주범은 자동차이며, 자동차에서 주로 많이 배출되는 질소산화물(NOx)과 탄화수소(HC) 및 디젤자동차에서의 입자상 물질(PM: Particulate Matter)등이 대기환경에 미치는 영향이 크므로 이러한 물질의 저감에 대한 요구가 점차 강화되어가고 있다. 특히, 디젤 엔진이 가솔린 엔진에 비해 대기오염의 주원인이라는 편견이 일반적으로 널리 알려져 있지만, 이는 눈에 보이는 Black smoke에 대한 거부반응이 있다는 점이다. 실제로 디젤 엔진의 유해 배출 성분 중에서 NOx는 가솔린과 비슷한 수준이나 HC와 CO성분은 상당히 적게 배출되고 있다. 또한, 디젤 엔진은 연료 경제성 및 지구 온난화의 원인인 CO$_{2}$ 배출이 적다는 장점이 있으므로 디젤 엔진에서 많이 배출되는 성분으로서 입자상 물질(PM) 및 NOx를 줄이는 방안이 요구되고 있다. 이를 저감시키는 방법은 여러가지가 있으나 분사계 측면에서 전자제어식 고압 연료 분사가 요구되고 있으며 이의 개발 필요성에 대해서 논하기로 한다.

• Journal of the KSME
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• v.34 no.12
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• pp.929-939
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• 1994

최근 환경문제와 관련하여 정제된 석유 연료가 아닌 천연가스와 같은 연료의 사용이 증가하면서 산업용 가스터빈의 연소기술에 대한 관심이 집중되고 있다. 가스터빈 연소로 생성되는, 환경을 위협하는 오염물은 연기, 수증기, 일산화탄소(CO), 미연 탄화수소, $NO_{x}$, $SO_{x}$ 등이 있다. 수증기 및 일산화탄소는 지구 온실화에 영향을 미치고 있으나 그다지 심각한 정도는 아 니며, $SO_{x}$는 독성이 있으나 연료 정제시 제거되어질 수 있다. $NO_{x}$는 지구의 오 존층을 파괴하여 생태계를 위협하기 때문에 오염 배출물중 가장 심각하게 고려되어지고 있다. 미국에서는 법으로 산업용 가스터빈의 $NO_{x}$의 양을 규제하고 있는데 15% 산소배출농도에 대하여 1984년에 75ppm에서 1993년에 30ppm으로 낮추어 규제하고 있다. 일본도 미국과 비슷한 수준으로 규제하고 있으며, 따라서 최근의 가스터빈 연소기술은 저 $NO_{x}$연소기에 대한 것으로 저$NO_{x}$연소에 관한 개론 및 가스터빈 연소기의 저$NO_{x}$화 방법, 그리고 미 국과 일본의 최근의 저$NO_{x}$연소기 개발동향에 대하여 다루고자 한다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.8
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• pp.823-833
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• 2010

For the study of thermophysical properties of kerosene for the liquid rocket and aviation fuels, the surrogate models are investigated. The density distributions based on the real gas equations of state(Soave modification of Redlich-Kwong and Peng-Robinson equation of state) and NIST SUPERTRAPP(extended corresponding state principle) are compared with the previous experimental results at supercritical conditions. The error range of thermophysical properties analyzed for the surrogate models as well. Peng-Robinson equation of state and extended corresponding state principle are especially accurate for the hydrocarbon fuels but the appropriate surrogate models need to be chosen to the operation conditions such as pressure and temperature.

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.690-694
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• 2015

Recently, direct formic acid fuel cells (DFAFC) among direct liquid fuel cells is studied actively. Economical hydrocarbon membranes alternative to fluorinated membranes for DFAFC's membrane are receiving attention. In this study, characteristics of sulfonated poly(ether ether ketone, sPEEK) and sulfonated poly(arylene ether sulfone, PAES) membranes were compared with Nafion membrane at DFAFC operation condition. Formic acid crossover current density of hydrocarbon membranes were lower than that of Nafion 211 fluorinated membrane. I-V performance of sPEEK MEA(Membrane and Electrode Assembly) was similar to that of Nafion 211 MEA due to similar membrane resistance each other. sPEEK MEA with low formic acid crossover showed higher stability compared with Nafion 211 MEA.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.1
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• pp.76-83
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• 2002

Mathematically and chemically simplified reaction scheme for n(heptane that simulates autoignitions of the end gases in spark ignition engines has been developed and studied computationally. The five(equation model is described, to predict the essential features of hydrocarbon oxidation. This scheme has been calibrated against autoignition delay times measured in rapid compression machines. The rate constants, activation temperatures, Ta, Arrhenius pre-exponential constants, A, and heats of reaction for stoichiometric nheptane/air has all been optimized. Comparisons between computed and experimental autoignition delay times have validated the present simplified reaction scheme. The influences of heat loss and concentration of chain carrier at the beginning of compression upon autoignition delay times have been computationally investigated.

• Journal of the Korean Society of Safety
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• v.31 no.2
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• pp.33-40
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• 2016

Liquid fuel can be easily exploded and release more energy of detonation than conventional explosives because it has different explosion mechanism. In order to analyze dispersion characteristics of liquid fuel for the safety purpose, two tests are conducted. First, pre-test, which is a computer simulation, is carried out by a software called ANSYS AUTODYN to eliminate the effect of a canister that usually causes irregular dispersion of the fuel. Second, field test is performed to find out the amount and density effect of bursting charge. High speed cameras are installed in front of the canister to visualize the mechanism. Velocity, area and radius of the dispersed cloud are measured by image processing software, these are shown that the amount of bursting charge affects cloud velocity and area but density is not a significant factor of cloud formation.

• Journal of ILASS-Korea
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• v.6 no.3
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• pp.23-31
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• 2001

An experimental study was carried out to understand the spray characteristics of three kinds(kerosene, heating oil & diesel) of hydrocarbon-fuels. Fuel temperature and injection pressure were main variables in the experiment. Fuel Temperature was changed to obtain various levels of fuel viscosity. Spray angle and spray length were measured by using LVS(Laser Vapor Screen) photographs. 1D PDPA system was used to measure droplet size & droplet velocity. In room temperature, spray characteristics of three kinds of fuels were good, especially in case the fuel injection pressure was more than $6Kgf/cm^2$ It was also found that spray characteristics were poor in case fuel kinematic viscosity was more than 5cSt.

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.189-192
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• 2015

An experimental study was conducted to find the effect of DBD plasma on the flammability limits of inert-gas-diluted fuel. The results showed that the concentration of diluting nitrogen at flammability limit increased when nitrogen-diluted methane and propane were reformed by plasma, while it decreased when nitrogen-diluted ethylene was reformed by plasma. Gas chromatography results suggested that the fuel type dependence of flammability limits is due to the difference in the concentrations of hydrogen and hydrocarbon species in reformed fuel.