• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.04a
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• pp.321-324
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• 2011

건자재로서 나무 결함 중의 하나는 화재에 대한 취약성이다. 본 연구의 목적은 한국에서 자란 리기다 소나무, 밤나무, 굴참나무, 느티나무의 연소성질을 시험하는 것과 건자재로서의 사용에 대한 바람직한 특성을 알아내는 것이며 연소억제를 위해 실온에서 3종류의 암모늄염 즉, ammonium sulfate, monoammonium phosphate, 그리고 diammonium phosphate를 20 wt% 수용액에 각각 리기다 소나무를 함침시켜 건조시킨 후 재료의 난연성을 시험하였다. 콘칼로리미터(ISO 5660-1)를 이용하였고 분석 결과로는 열방출랑을 비롯하여, 가스방출량, 발화점 등을 측정하여 비교분석하였다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2012.04a
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• pp.167-169
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• 2012

본 연구는 정수기 화재의 원인 판정을 위한 지식기반을 구축하기 위해서 인위적 착화가 발생했을 때의 연소 확산 패턴을 해석하였다. 실험이 재현되는 동안 외부에서 인위적인 에너지의 공급은 없었으며, 정수기는 정상 작동 상태를 유지시켰다. 인위적 화염으로 착화되어 50[sec] 경과하였을 때까지 불꽃은 외부에서 관측되지 않았다. 그러나 120[sec] 정도 경과되었을 때 일순간 화염은 확산되기 시작하였으며, 부분적인 소락이 발생되는 것이 관측된다. 화염이 180[sec] 동안 진행되었을 때 강제로 진압된 후 연소패턴 분석에서 최초의 착화점을 기준으로 정확한 브이패턴(V-pattern)이 형성되었으며, 외부에서 화염이 공격되었을 때와 확연한 차이가 있음을 알 수 있다. 또한 정수기 후면에 설치된 방열판의 열화 특성 분석에서 화열의 공격방향 판정이 가능한 것을 알 수 있었다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.25 no.2
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• pp.82-86
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• 1989

This paper is concerned with the effects of temperature of diesel fuel on combustion characteristics and engine performance in a home-made precombustion diesel engine for small-sized fishing boat. The results may be summarized as follows: 1. The fuel injection timing was delayed with increase in temperature for diesel fuel, and remarkably delayed at low load. 2. The point of maximum pressure was delayed with increase in temperature for diesel fuel, the maximum pressure decreased with increase in temperature for diesel fuel but increased with increase in load. 3. The brake specific fuel comsumption (BSFC) decreased with increase in load, the optimum temperature of the heated fuel was about 15$0^{\circ}C$. 4. The smoke emissions increased with increase in load and temperature for diesel fuel.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.8
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• pp.75-83
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• 2005

A steady transonic dilute premixed combustion in a diverging channel is investigated by using asymptotic analysis. This model explores the nonlinear interactions between the near-sonic speed of the flow, the small changes in geometry from a straight channel, and the small heat release due to the one-step first-order Arrhenius chemical reaction. The reactive flow is described by a nonhomogeneous transonic small-disturbance (TSD) equation coupled with an ordinary differential equation for the calculation of the reactant mass fraction in the combustible gas. Also the asymptotic analysis reveals the similarity parameters that govern the reacting flow problem. The results show the complicated nonlinear interaction between the convection, reaction, and geometry effects and its effect on the flow behavior.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.652-655
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• 2010

BBU attached to the 155mm is the weapon system for the extension of range through the reduction of base drag. This research focus on the development of inhibitor formulation changing cure agent from DDI to IPDI. Development process is as follows. First, the formulation test about basic property Second, the study on the application of process. Third, the tests for the quality and aging properties. The test results are satisfied with the all of the requirments. In results, this research is contributed to the stable manufacturing in the instability of supplying of cure agent.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.390-393
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• 2010

The thermal decomposition rate of ammonium perchlorate with 3% of yellow iron oxide, FeOOH was found to be much faster than with red iron oxide, $Fe_2O_3$. By applying yellow and red iron oxide as a burning rate modifier to HTPB/AP propellant, burning rate of the HTPB/AP propellant with yellow iron oxide was shown to be 10 ~ 25% faster than with red iron oxide. There was no special difference in viscosity and hardness buildup of yellow and red oxide added HTPB/AP formulations.

• Korean Chemical Engineering Research
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• v.56 no.4
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• pp.474-478
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• 2018

For process safety, fire and explosion characteristics of combustible materials handled at industrial fields must be available. The combustion properties for the prevention of the accidents in the work place are flash point, fire point, explosion limit, and autoignition temperature (AIT) etc.. However, the combustion properties suggested in the Material Safety Data Sheet (MSDS) are presented differently according to the literatures. The accurate combustion properties are necessary to safely treatment, transportation and handling of flammable substances. In the chemical industries, n-ethylaniline which is widely used as a raw material of intermediate products and rubber chemicals was selected. For safe handling of n-ethyl aniline, the flash point, the fire point and the AIT were measured. The lower explosion limit (LEL)of n-ethylaniline was calculated using the lower flash point obtained in the experiment. The flash points of n- ethylaniline by using the Setaflash and Pensky-Martens closed-cup testers measured $77^{\circ}C$ and $82^{\circ}C$, respectively. The flash points of n-ethylaniline using the Tag and Cleveland open cup testers are measured $85^{\circ}C$ and $92^{\circ}C$, respectively. The AIT of the measured n-ethyl aniline by the ASTM E659 apparatus was measured at $396^{\circ}C$. The LEL of n-ethylaniline measured by Setaflash closed-cup tester at $77^{\circ}C$ was calculated to be 1.02 vol%. In this study, it was possible to predict the LEL by using the lower flash point of n-ethylaniline measured by closed-cup tester. The relationship between the ignition temperature and the ignition delay time of the n-ethylaniline proposed in this study makes it possible to predict the ignition delay time at different ignition temperatures.

• Journal of Convergence for Information Technology
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• v.11 no.7
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• pp.111-117
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• 2021

This research work is to suggest the experimental results capable of solving an initial unsuitability of combustion and environment in a constant volume combustion chamber by using LFG(Land Fill Gas) which consists of 40% CO₂ and 60% CH₄. The experimental condition is set as 0.9~1.6 of air-fuel ratio, 3bar of combustion pressure, 25℃ of room temperature, methane for using gas, and 2.5~4.5 of Pre-chamber hole sizes. As a result, it can be seen that diffusion of initial flame is significantly increased by M3.0 model comparing with other one. The reason for the characteristics is that orifice effect is extremely improved by 0.9, 1.0, and 1.2 of air-fuel ratio comparing with other one. Consequently, this experiment is shown that M3.0 model is partially capable of improving combustion performance than a conventional ignition plug in case of applying to LFG with Pre-chamber design.

• Fire Science and Engineering
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• v.29 no.4
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• pp.67-72
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• 2015

A series of fire tests was conducted to examine the fire characteristics of flaming and smoldering combustion of engineered wood products, which have been widely used for furniture and finishing materials in buildings. The engineered wood products of MDF, plywood, and chipboard were ignited by a radiant cone heater with incident heat flux of $50kW/m^2$. During the fire test, key parameters representing the fire characteristics such as the heat release rate, yield rate of combustion product, and effective heat of combustion were quantified in terms of thickness. The tests show two peak points of HRRPUA due to lateral fire propagation in the initial stage, followed by later fire penetration through the specimen thickness. The mass loss rate of flaming combustion was 5 times higher than that of smoldering combustion, while the CO yield rate of smoldering combustion was 10 times higher than that of flaming combustion. This study can contribute to the understanding of fire behavior of wood combustibles and provide useful data for fire analysis.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.4
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• pp.52-58
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• 2007

The irregular fuel surface was observed by the visualization of hybrid rocket combustion. Even though the test condition maintained oxidizer rich environment, the irregular dark fuel surface was formed as the result of incomplete combustion. In order to investigate the correlation of the characteristics of oxidizer flow and the irregular fuel surface, various flow conditions were imposed such as swirl flow, induced swirl flow by helical fuel configuration and straight flow. Test results revealed no correlation was found between oxidizer flow condition and irregular fuel surface. And this can be a commonly observed phenomena in the tests with different fuel/oxidizer combination. Thus, the irregular fuel surface can be a result of the interaction of blowing flow of vaporized fuel and the boundary layer of oxidizer flow. A further study will be required to confirm the assumption for the formation of irregular fuel surface.