• Journal of Energy Engineering
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• v.24 no.2
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• pp.79-83
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• 2015

Hydrogen has long been recognized as a fuel having some unique and highly desirable properties, for application as a fuel in engines. Hydrogen has some remarkably high values of the key properties for transport processes, such as kinematic viscosity, thermal conductivity and diffusion coefficient, in comparison to those of the other fuels. Such differences together with its extremely low density and low luminosity help to give hydrogen its unique diffusive and heat transfer characteristics. The thermodynamic and heat transfer characteristics of hydrogen tend to produce high compression temperatures that contribute to improvements in engine efficiency and lean mixture operation.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.103.2-103.2
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• 2010

Biodiesel was well known for eco-friendly alternative fuel for petrodiesel. But biodiesel have disadvantage such like it was derived from food resource which was high price. In this study, We synthesized the biodiesel from duck's oil which was food trash via transesterification under base catalyst. After analytic result of density, kinematic viscosity, cold temperature characteristics, lubricity and cetane number which were main fuel characteristics, this duck's biodiesel have enough to fuel specification for except of domestic winter season.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.368-372
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• 2005

The variation of regression rate of single port hybrid rocket was studied with various fuel. As fuel, PE, PMMA were used and gas oxygen as oxidizer. The regression rate depends on but flow rates of oxidizer also thermodynamic properties of fuel. In this study, the empirical relation for regression rate of solid fuel were found with mass transfer coefficient(B number) and oxidizer flow rate.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.702-704
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• 2011

For the representative of the poor performance of liquid fuel(Jet A-1), the physical properties effests of different additive ratios in the liquid fuel have been investigated. The mixed liquid fuel could be analyzed by principal factor of liquid fuel such as, density, viscosity and caloric value. This additives will be usefully applied to high energy density liquid fuel development.

• Nuclear Engineering and Technology
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• v.52 no.3
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• pp.614-620
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• 2020

In a previous study, delayed hydride cracking (DHC) assessment of pressurized water reactor (PWR) spent fuel during dry storage using the threshold stress intensity factor (K_IH) was performed. However, there were a few limitations in the analysis of the cladding properties, such as oxide thickness and mechanical properties. In this study, those models were modified to include test data for irradiated materials, and the cladding creep model was introduced to improve the reliability of the DHC assessment. In this study, DHC susceptibility of PWR spent fuel during dry storage depending on the axial elevation was evaluated with the improved assessment methodology. In addition, the sensitivity of affecting parameters such as fuel burnup, hydride thickness, and crack aspect ratio are presented.

• Nuclear Engineering and Technology
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• v.43 no.6
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• pp.509-522
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• 2011

FRAPCON-3.4a and FRAPTRAN 1.4 are the most recent versions of the U.S. Nuclear Regulatory Commission (NRC) steady-state and transient fuel performance codes, respectively. These codes have been assessed against separate effects data and integral assessment data and have been determined to provide a best estimate calculation of fuel performance. Recent updates included in FRAPCON-3.4a include updated material properties models, models for new fuel and cladding types, cladding finite element analysis capability, and capability to perform uncertainty analyses and calculate upper tolerance limits for important outputs. Recent updates included in FRAPTRAN 1.4 include: material properties models that are consistent with FRAPCON-3.4a, cladding failure models that are applicable for loss-of coolant-accident and reactivity initiated accident modeling, and updated heat transfer models. This paper briefly describes these code updates and data assessments, highlighting the particularly important improvements and data assessments. This paper also discusses areas of improvements that will be addressed in upcoming code versions.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.77-80
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• 2006

Chloromethylated polysulfone(CMPSf) and a number of mono- and diamine compounds were used to prepare anion-exchange membranes(AEMs) and an ionomer binder solution. The properties of the AEMs were investigated such as $OH^-$ conductivity, water content and dimension stability. Chloromethylation and amination of PSf were optimized in terms of the properties. Membrane-electrode assemblies were fabricated using anion-exchange membranes and the ionomer binder for solid alkaline fuel cells and direct borohydride fuel cells.

• Journal of Power System Engineering
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• v.12 no.2
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• pp.12-17
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• 2008

Biodiesel fuel(BDF) which is easily produced from vegetable oils such as soybean oil and rice bran oil can be effectively used as an alternative fuel in diesel engine. But biodiesel fuel can affect the performance and emissions in diesel engine because it has different chemical and physical properties from diesel fuel. To investigate the combustion characteristics of biodiesel fuel as an alternative fuel for D.I. diesel engine, the experiments were carried out at the three-cylinder, four stroke D.I. diesel engine with T/C. Experimental parameters adopted a conventional diesel fuel and a blend of biodiesel fuel derived from soybean. As a result of experiments in a test engine, BSFC with blend of BDF resulted in higher than with diesel fuel. The ignition delay decreased with blend of BDF than with diesel fuel.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.129.2-129.2
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• 2010

AEM which were used for solid alkaline fuel cell(SAFC) were prepared by photo polymerization in method pore-filling with various quaternary ammonium cationic monomers and crosslinkers without an amination process. Their specific thermal and chemical properties were characterized through various analyses and the physico-chemical properties of the prepared electrolyte membranes such as swelling behavior, ion exchange capacity and ionic conductivity were also investigated in correlation with the electrolyte composition. The polymer electrolyte membranes prepared in this study have a very wide hydroxyl ion conductivity range of 0.01 - 0.45S/cm depending on the composition ratio of the electrolyte monomer and crosslinking agent used for polymerization. However, the hydroxyl ion conductivity of the membranes was relatively higher at the whole cases than those of commercial products such as A201 membrane of Tokuyama. These pore-filling membranes have also excellent properties such as smaller dimensional affects when swollen in solvents, higher mechanical strength, lowest electrolyte crossover through the membranes, and easier preparation process compared of traditional cast membranes. The prepared membranes were then applied to solid alkaline fuel cell and it was found comparable fuel cell performance to A201 membrane of Tokuyama.

• Journal of ILASS-Korea
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• v.17 no.3
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• pp.121-127
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• 2012

The study is to investigate the mixing stability, fuel properties, and macroscopic spray characteristics of diesel-gasoline blended fuels in a common-rail injection system of a diesel engine. The test fuels were mixed diesel with gasoline fuel, which were based volume fraction of gasoline from 0 to 100% in 20% intervals. In order to analyze the blended effect of gasoline to diesel fuel, the properties of test fuels such as density, viscosity, and surface tension were measured. In addition, the spray behavior characteristics were studied by investigating the spray tip penetration and spray angle using a spray images through a spray visualization system. It was revealed that the density, kinematic viscosity and surface tension of diesel-gasoline blending fuels were decreased with the increase of gasoline fuel. The injection quantity of test fuels were almost similar level at short energizing duration condition. On the other hand, the increase of energizing duration shows the decrease of injection quantity compared to short energizing duration. The test blending fuels have similar growth in Spray tip penetration and Spray cone angle.