• Fire Science and Engineering
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• v.28 no.3
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• pp.20-28
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• 2014

Effect of radiation models on the suppression limits in counterflow $CH_4$/air diffusion flame was numerically investigated with fundamental experiments for the numerical validation. $N_2$ and $CO_2$ were considered as extinguishing agents. The differences in extinguishing concentration between OTM and SNB radiation models which have different accuracy levels were examined. As a result, there is no considerable difference in extinguishing concentration for the $N_2$ dilution as the radiation models with different accuracy levels were used. As the $CO_2$ having strong radiative effect was diluted in the low strain flames, however, the radiation model with high predictive accuracy such as SNB should be used. In particular, the $CO_2$ dilution in fuel stream leads to the significant difference in extinguishing concentration between OTM and SNB models. Therefore, it is necessary that the radiation model should be reasonably chosen with the consideration of numerical accuracy and computational time for the prediction of extinguishing concentration.

• Journal of the Korean Institute of Gas
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• v.15 no.3
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• pp.31-38
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• 2011

In this study, we investigate simulation studies to confirm the removal of smoke through ventilation when the subway car is on fire and stopped in an underground subway tunnel, by using Fire Dynamics Simulator (FDS) which is being upgraded by NIST. The structure of subway tunnel and train for simulation modeling are based actual data from Seoul metropolitan subway. The main purpose of this study is to assure the removal efficiency of the ventilation when changing the ventilation capacity between 2.0 m/s and 3.0 m/s. The results of the study shows that carbon monoxide (CO) and carbon dioxide ($CO_2$) are reduced by about 35% as the ventilation capacity is increased by 0.5 m/s. This study also performs the grid sensitivity verification of FDS for improved accuracy of the results. To find the effective size of the grid, three cases are simulated and the results are compared.

• Tunnel and Underground Space
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• v.7 no.2
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• pp.100-107
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• 1997

In case of a fire outbreak in a uni-directional road tunnel, the flow of traffic immediately behind the fire disaster will be stalled all the way back to the entrance of the tunnel. Furthermore, when the vehicle passengers try to flee away from the fire toward the entrance of the tunnel, the extremely hot fume that propagates in the same direction will be fatal to the multitudes evacuating, but may also cause damage to the ventilation equipments and the vehicles, compounding the evacuation process. This paper will present the 3-dimensional modelling analysis of the preventive measures of such a fume propagation in the same direction as the evacuating passengers. For the analysis, the fire hazard was assumed to be a perfect combustion of methane gas injected through the 1 m X 2 m nozzle in the middle of the tunnel, and the product of $CO_2$ as the indicator of the fume propagation. From the research results, when the fire hazard occurred in middle of the 400 m road tunnel, the air density decreased around the fire point, and the maximum temperatures were 996 K and 499 K at 210 m and 350 m locations, respectively, 60 seconds after fire disaster occurred, when the fumes were driven out only towards the exit-direction of the tunnel. By tracing the increase of $CO_2$ level over 1% mole fraction, the minimum longitudinal ventilation velocity was found to be 2.40 m/sec. Furthermore, through Analysis of the temperature distribution graphs, and observation of the cross-sectional distribution of $CO_2$ over 1% mole fraction, it was found that the fume did not mix with the air, but rather moved far in a laminar flow towards exit of the tunnel.

• Journal of the Society of Disaster Information
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• v.12 no.4
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• pp.342-349
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• 2016

The objectives of this study is analysis of the characteristics of fire risk and survey of narrow dwelling space(the Karaoke, Gosiwon etc). The narrow dwelling space has special structure characteristics; the narrow and the complex escape rote. Gosiwon have very separate and exclusive space room, so have the problem a suppression of fire. Furthermore almost Karaokes located in basement have a complex and limitary escape rote. Therefore we should research and development the exploration equipment that search a source of the fire and a emergency rescuer in the scene of the fire.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1275-1281
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• 2011

This paper presents synthetic circumstantial judgement system that detects and predicts a fire in subway station. Unlike conventional fire surveillance systems that judge the fire or not through smoke, CO, temperature or variation of temperature, a proposed system discovers a fire more easily or gives the alarm high possibility of fire to operator through recognition of fire levels based on Fuzzy Inference System using by FCM and information of objects from video data.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2007.11a
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• pp.219-224
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• 2007

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2007.04a
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• pp.141-145
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• 2007

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2007.04a
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• pp.159-165
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• 2007

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2005.09a
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• pp.125-128
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• 2005

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.127-130
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• 2011

화재 시뮬레이션이라 함은 현실적으로 화재의 재현은 불가능한 관계로 컴퓨터를 이용하여 화재모델을 표현하는 방법을 취하는 것으로 이것을 시뮬레이션이라 하며, 이를 통하여 대상물의 특징을 해석 규명하여 현실화 한 것이 화재 시뮬레션이다. 나날이 증가하고 있는 화재시뮬레이션의 필요와 중요성에도 불구하고 국내에선 개발자체가 지지부진한 상태이며, 금번 화재감식 시뮬레이션의 개발에 앞서 외국에서 사용되고 있는 화재 시뮬레이션의 비교 분석을 통하여 미력이나마 시뮬레이션 개발에 도움이 되고자 한다.