• Journal of Korean Society of Steel Construction
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• v.25 no.6
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• pp.587-599
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• 2013

A simple but accurate analytical method to evaluate the fire resistance of unprotected concrete filled tubular (CFT) columns under standard fire condition is proposed based on the fire design framework of EC4. To this end, the accuracy of the current tabulation method for the temperature prediction proposed by Lawson et al. was first critically evaluated, and a new prediction equation for the temperature gradient across the CFT section was then proposed based on available test and finite element analysis results. Overall, the axial strength predicted by using the proposed equation under the general fire design framework of EC4 was more accurate than that based on existing methods and appeared reasonable for design purposes. The results of this study are directly usable for the more rational fire analysis and design of unprotected CFT columns.

• Fire Science and Engineering
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• v.33 no.5
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• pp.1-6
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• 2019

The recent development of biofuel production technology facilitates the widespread use of bioethanol and biodiesel by mixing them with fossil fuels. However, the use of these new blended fuels in combustion could result in severe safety problems, such as fire and explosion. In this study, numerical simulation was performed on the well-stirred reactor (WSR) to simulate the autoignition temperature (AIT) in homogeneous combustion and clarify the effect of ethanol addition on the AIT, the most important property for assessing the potential for fire and explosion. Response surface methodology (RSM) was introduced as a design of experiment (DOE), enabling the AIT to be predicted and optimized systematically with respect to three independent variables: ethanol mole fraction, equivalence ratio, and pressure. The results show that the autoignition temperature primarily depends on the ethanol mole fraction and pressure, while the effects of the equivalence ratio are independent of the AIT. RSM accurately predicted the experimental AIT, indicating that this method can be used to effectively predict the key properties involved in fires and explosions.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.190-190
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• 2011

사회 다변화 및 급속한 경제성장과 도시밀집화로 인하여, 화재의 발생으로 인하여 막대한 인명피해 및 대규모의 재산상의 피해가 지속적으로 발생하고 있다. 이러한 화재의 피해를 예측하기 위해서는 실제 규모의 화재실험이 매우 유용하지만, 막대한 비용과 현실적 제약조건으로 인하여 실제 실험에는 많은 어려움이 따른다. 따라서 막대한 예산이 소요되는 실제규모의 화재실험의 대체방법으로 실제를 모사하는 축소모형 화재모의실험 및 컴퓨터를 이용한 화재 시뮬레이션 기법이 널리 이용되고 있다. 본 논문에서는 범용 컴퓨터를 이용한 화재 시뮬레이션 기법(CFAST)을 이용하여 수직 공간 구성을 가지는 단독주택의 화재 성상을 검토하였다. 시뮬레이션 모델로는 단독주택을 대상건물로 하여 2층으로 수직 공간을 가지는 단독주택 건물에 대한 모의 화재 시뮬레이션을 수행 하였다. 화재 시뮬레이션 결과는 각 구획실별 온도, 일산화탄소량, 공기 중 산소량 등을 도출하여 기존 이론에 의한 화재성장 그래프와 시뮬레이션 데이터를 비교하여 정확도를 검토하였다. 본 논문에서는 두가지의 시나리오를 작성하여 화재 시뮬레이션 프로그램의 결과 값을 분석하였다. (1) 시나리오 1 : 화재시뮬레이션 대상건물 1층 거실(2번방)에서 스프링클러 미 설치시 화재가 발생한 경우를 가정하여 수평방향인 3번방과 수직방향인 7번방의 화재 확산 피해정도를 살펴보고, 화재 그래프의 이론값과 실험값의 차이를 비교하여 그 정합성을 검토하였다. 발화물질은 Curtain, TV set, Sofa, Table으로 하며 시간은 60초 간격으로 총 3600초(1시간)를 분석 하였고, 발화지점의 온도, 일산화탄소, 공기중 산소 농도를 분석하였다. (2) 시나리오 2 : 시나리오 1과 동일한 화재발현 조건으로 스프링클러가 설치되어 있을 때 화재 발생 했을 경우, 수평방향인 3번방과 수직방향인 7번방의 화재 확산 피해를 시나리오 1과 비교 검토 하였다. 기존 이론에 의한 화재 성장 그래프와 이번 시뮬레이션 결과값을 토대로 만든 그래프 형태를 비교해보면 두 그래프의 형태가 비슷한 형태를 나타내어 Flash Over 현상과 Back Draft 현상이 이론값과 같은 경향을 나타내고 있음을 확인 할 수 있었다. 따라서, 본 논문에서 수행한 화재 시뮬레이션 기법으로 건축물의 실제 화재시의 피해정도를 예측하는 데 유용하게 활용될 것으로 판단된다.

• Fire Science and Engineering
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• v.31 no.5
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• pp.1-6
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• 2017

The fire and explosion properties of combustible materials are necessary for the safe handling, storage, transportation and disposal. Typical combustion characteristics for process safety include auto ignition temperature(AIT). The AIT is an important index for the safe handling of combustible liquids. The AIT is the lowest temperature at which the material will spontaneously ignite. In this study, the AITs and ignition delay times of n-pentanol and p-xylene mixture were measured by using ASTM E659 apparatus. The AITs of n-pentanol and p-xylene which constituted binary system were $285^{\circ}C$ and $557^{\circ}C$, respectively. The experimental AITs and ignition delay times of n-pentanol and p-xylene mixture were a good agreement with the calculated AITs and ignition delay times by the proposed equations with a few A.A.D. (average absolute deviation). Therefore, it is possible to estimate the AITs and ignition delay times in other compositions of n-pentanol and p-xylene mixture by using the predictive equations which presented in this study.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2012.04a
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• pp.397-399
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• 2012

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2000.04a
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• pp.80-85
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• 2000

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.163-166
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• 2011

본 연구는 Zone Model을 활용하여 장대도로터널의 화재성상 예측방법의 고찰을 목적으로 1/5 Scale 모형실험 및 MLZSUZUKI 결과 분석과 CFD와 MLZ의 비교 분석을 실시하였다. Modeling한 모형터널의 해석시간이 MLZ 1분, FDS 약 6시간으로 CFD에 비하여 360배의 시간 감소와 다층으로 구분하여 구간의 온도변화 및 환기풍에 의한 열기류의 움직임 등의 상황이 해석됨으로 향후 MLZ을 활용하여 터널화재의 위험성 예측에 용이할 것으로 판단된다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.1
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• pp.255-261
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• 2013

In this paper, we developed and tested a program for prediction flash fire in a combat system. Purposes of the program are flash fire prediction of combat system for analysis vulnerability and survivability, and visualization for fire-related information. To do this, we defined critical components of the combat system which has probabilities of flash fire occurrence, and proposed Flash Fire Probability Tree which is based on Fault Tree Analysis(FTA). The program visualizes positions of critical components in combat system, positions of penetrated components, selected Flash Fire Probability Tree, temperature profile, and tables for properties of matters.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.11a
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• pp.43-48
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• 1997

The smoke filling process for the atrium space containing a fire source is simulated using two types of deterministic fire modus: Zone model and Field model. The zone mode used is the CFAST(version 1.6) mode developed at the Building and Fire Research laboratories, NIST in the USA. The lied model is a self-developed fire field model based on Computational Fluid Dynamics(CFD) theories. This article is focused on finding out the smoke movement and temperature distribution in atrium space which is cubic in shape. A computational procedure for predicting velocity and temperature distribution in fro-induced flow is based on the solution, in finite volume method and non-staggered grid system, of 3-dimensional equations for the conservation of mass, momentum, energy, species and so forth. The fire model i. e. Zone model and Field model predicted similar results for Ire clear height and the smoke layer temperature.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.749-755
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• 2022

Electricity is essential energy in modern society, such as being used in various industries. However, the rate of fires occurring on electric wiring to deal with it is very high. In this work, we implemented a system to predict the temperature change of an electric circuit through analysis using various regression models. To do so, we collected the temperature data of 27 types of magnetic switches which control electric circuits as well as trained the regression models by using the collected temperature data. In our experiments, we confirmed that the regression models can be trained at a sufficiently usable level since the difference between the actual temperature and predicted temperature is about 4℃. The results of our work will be useful to predict the temperature of electric circuits and preventing fires on them.