• Fire Science and Engineering
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• v.32 no.4
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• pp.7-16
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• 2018

In this study, the prediction performance of design fire curves (DF) was evaluated for gas fires in a compartment by using CFAST. The CFAST simulations adopted the 2-stage DF suggested by the previous study and the Quadratic and Exponential DF suggested by Ingason. It was found by comparing the simulation and experimental results that the overall prediction performance of the design fire cures for the spatially-averaged temperature and concentrations of $O_2$ and $CO_2$ was, from the most reasonable to the most inaccurate, 2-stage DF > Quadratic DF > Exponential DF. The CFAST simulation could not predict for the difference in the spatially-averaged temperature and concentrations of $O_2$ and $CO_2$ at door and inner side locations in a compartment. The CFAST simulations also showed a limitation in the prediction of the spatially-averaged temperature at lower layer and the concentration of CO.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1354-1361
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• 2007

The evacuation simulation study was performed with the boundary condition of a fire simulator, referring to Dae-gu Subway Fire Accident which was a real station fire. The subway station was modelled from B3F station building to B2F waiting room in fire simulation. Also, a fire simulation were performed with CFAST and FLUENT. In CFAST, the total 29 zones were divided into 18 station buildings in B3F and 11 station buildings in B2F. In FLUENT, the simulated space had the same establishment as zone of CFAST. The study focused on possibility for application of fire simulation in underground station by comparing the resulted values from two simulators. For application of fire effect, the fire data were loaded directly to EXODUS in the case of CFAST and performed a passenger evacuation simulation. In the case of FLUENT, Out Data values of a fire simulation were difficult to be compatible with EXODUS. Two resulted values of passenger evacuation simulation by fire simulation were compared with the Dae-gu Subway Fire Accident in reality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.2533-2538
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• 2014

In this study, 2-zone model CFAST software was used to predict the fire hazard of karaoke. Model is a three-dimensional unsteady state. Accuracy of CFAST is verified by comparing result of CFAST analysis with result of real fire experiment. For analysis results, the oxygen concentration were reduced to 10% within 5 minutes in room 5, the carbon dioxide concentration were increased to 5%. Therefore, at the enclosed space like karaoke, we can predict that dangerous situation would occur and people be suffocated because of toxic gas.

• Fire Science and Engineering
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• v.32 no.2
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• pp.7-16
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• 2018

In this study, the previous design fire curve for fire simulation was modified and re-suggested. Numerical simulations with the FDS and CFAST were performed for the n-heptane and n-octane pool fires in the ISO 9705 compartment to evaluate the prediction performances of the previous 1-stage and modified 2-stage design fire curves. The numerical results were compared with the experimental temperature and concentrations of $O_2$ and $CO_2$. The FDS and CFAST simulations with the 2-stage design fire curve showed better prediction performance for the variation of temperature and major species concentration than the simulations with 1-stage design fire curve. Especially, the simulations with the 2-stage design fire curve agreed with the experimental temperature more reasonably than the results with the 1-stage design fire curve. The FDS and CFAST simulations showed good prediction performance for the temperature in the upper layer of compartment and the results with the FDS and CFAST were similar to each other. However, the FDS and CFAST showed poor and different prediction performance for the temperature in the lower layer of compartment.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.444-449
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• 2008

Fire model shall be verified and validated to reliably predict the consequences of fires within its limitations. This study aims to predict pool fire phenomena with two rooms using CFAST and to compare CFAST simulation results with PRISME experimental data which can be applicable to the fire of nuclear power plant facility. Five different mass loss rate(MLR) are used in the simulation and the simulated results of specific quantities such as temperature, chemical composition are compared to the experimental data. From this study, the CFAST simulation results with the proper MLR show better similarity and trend with pool fire experimental data.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.2
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• pp.339-345
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• 2010

This study has purpose of minimizing damage from fire incident as analyzing the fire characteristic about fire incident of multi-use hostels, which is increasing recently. For this, CFAST, a verified analysis program for the fire incident was employed to prove the logicality of the study by comparing with a established result of the research work and working the fire simulation for an apartment house. On the basis of this, the study will help to improve safety of fire by analyzing the fire characteristic of Karaoke and Gosiwon which are typical model of multi-use hostels and by establishing how to deal with the fire incident.

• Fire Science and Engineering
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• v.18 no.4
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• pp.64-71
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• 2004

This paper describes the result of the pump room fire analysis of the nuclear power plant using CFAST fire modeling code developed by NIST. The sensitivity studies are performed over the input parameters of CFAST: the constrained or unconstrained fire, Lower Oxygen Limit (LOL), Radiative Fraction (RF), and the opening ratio of the fire doors. According to the results, a pump room fire is the ventilation-controlled fire, so it is adequate that the value of LOL is 10% which is also the default value. It is anlayzed that the Radiative Fraction does not affect the temperature of the upper gas layer. It is appeared that the integrity of the cable located at the upper layer is maintained except for the safety pump at the fire area and the Conditional Core Damage Probability (CCDP) is 9.25E-07. It seems that CCDP result is more realistic and less uncertain than that of Fire Hazard Analysis (FHA).

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.4
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• pp.383-388
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• 2014

This study predicts damaging risk factors in apartment fire situation by using CFAST. The software was developed by Building and Fire Research Lab, that is government affiliated organization of the National Institute of Standards Technology. This analysis scenarios werec well verified by experimental results. Situation of the living room and the second room as well as the bedroom tends to be qualitatively the same with the experimental data. In case of apartment fire, it is predicted that they have been got into trouble with dizziness, badly vomiting and paralysis symptoms due to short oxygen and excessive carbon dioxide when persons were left out in the living room or second room.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.189-189
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• 2011

최근 공동주택은 보편적인 도시주거 유형으로 자리매김 하고 있지만, 성장 위주의 경제 산업 정책에 따른 안전의식미약, 사회구조개편에 따른 급격한 증가, 생활환경 변화와 에너지 사용 증가 등 화재 유발인자의 다양화로 인해 인적 물적 피해가 증가하고 있는 실정이다. 특히 다른 건물들과는 달리 공동주택의 거주자가 유아, 노인, 신체장애자 등 다양한 인적 구성의 형태로 이루어져 있어서 화재 발생 건수에 비해 인명피해가 월등히 높은 편이다. 공동주택에서의 화재에 대한 위험성을 인식하고, 그에 대한 인적 물적 피해를 최소화하기 위한 대책 마련이 시급하다. 본 논문은 CFAST(Consolidated Model of Fire Growth and Smoke Transport)를 사용하여 공동주택을 대상으로 실물 화재 실험을 실시하고 공간화재에서의 화재 성상을 파악하여 화재 시 개구부의 개폐 여부에 따라 발생되는 산소와 이산화탄소의 농도와 온도가 인체에 미치는 영향에 대해 알아본다. 개구부를 개방 했을 경우에 외부창문의 개폐 여부에 상관없이 모든 방의 온도 분포가 뚜렷하게 나타났지만 개구부를 폐쇄 할 경우에는 발화지점인 거실의 온도 분포만 나타났다. Flashover현상과 Back Draft현상은 개구부의 개폐여부에 상관없이 외부 창문을 폐쇄 했을 경우에 나타났지만 특히 모든 개구부와 외부창문을 폐쇄 했을 경우에 더욱 뚜렷하게 나타났다. 각 실은 점화 후 4분경에 최고 온도를 보였으며 다른 방에 비해 발화지점인 거실의 온도가 가장 높게 나타났다. 온도에 의해서는 두 가지 영향이 일어날 수 있는데, 하나는 비교적 장시간에 걸쳐 발생하는 열응력이고, 다른 하나는 짧은 시간에 발생할 수 있는 화상이다. 만약 피부온도가 $45^{\circ}C$에 이르면 인체는 고통을 느끼게 되며, 이보다 더 높은 온도에서는 깊은 피부조직까지 손상을 줄 수 있다. 움직이지 않는 사람에 대한 고통 유발 임계온도는 약 $200^{\circ}C$이며, 인체는 땀의 발산으로 온도에 대한 내성이 증가하지만 이체가 장시간 열을 받으면 사망에 이를 수 있다. 결론적으로 공동 주택을 대상으로 CFAST를 이용해 분석한 결과 플래쉬오버 현상으로 인해 화재가 성장하여 급격히 온도가 상승하다가, 산소 부족으로 인해 화재가 성장하지 않고 온도가 떨어지는 것을 알 수 있다. 화재 시 온도, 산소, 이산화탄소를 고려하였을 때 약 3분 이내에 대피해야 온도 및 가스로 인한 피해를 줄일 수 있을 것으로 판단된다.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1807-1813
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• 2007

The study aims at analyzing an underground station refuge model using EXODUS, one of the refuge simulation programs. The model for simulation is the Daegu Subway (Joongang-ro station). The details of the accident are referred to as the simulation condition the refuge time of traveling from the $3^{rd}$ basement platform to the $1^{st}$ basement is mainly calculated, with passengers numbering 1,000 including 329 at car 1079, 320 at car 1080, and 360 who are not on board. Reference data is used to set up the position of passengers. CFAST fire simulator is also used, and a fast curve among the $t^2$ growth curves, selected as fire growth scenario. The zone is divided into a total of 24 including 18 at the $3^{rd}$ basement platform and 6 at the $2^{nd}$ basement the $1^{st}$ basement is excluded in the fire simulation, however.