• Fire Science and Engineering
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• v.28 no.3
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• pp.29-33
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• 2014

Cleanroom fires were simulated by using Fire Dynamics Simulator. A grid size of $0.5{\times}0.5{\times}0.2m^3$ was selected following review of grid sizes. Fires in three large cleanrooms were investigated to confirm safety by applying the requirements on temperature, visibility, and carbon monoxide concentration in performance based design. The worst situation without sprinkler system and air flow of 0.1 m/s downward in the cleamrooms was considered. It was confirmed that all the three cleanrooms were safe in case without sprinklers since the temperature was below the safety requirement. Decrease in visibility and carbon monoxide concentration due to the fires were negligible.

• Fire Science and Engineering
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• v.23 no.5
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• pp.103-109
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• 2009

In this study, fire simulations on the under-ventilated compartment fires have been conducted using the Fire Dynamics Simulator (FDS Ver. 5.2) and its prediction performance on the thermal and combustion chemical characteristics has been discussed. The temperature and chemical species concentrations in the upper layer of methane, heptane, and toluene fires located in a 2/5 scale compartment based on the ISO-9705 standard room are predicted and compared with the previously published experimental data. The results showed that the FDS simulations reproduced well the temperature of the ceiling and the mixture fraction in the upper layer under the well-ventilation conditions. For the under-ventilated fires, which were taken place due to the insufficient oxygen entrainment, the prediction by the FDS significantly under-estimated the production of carbon monoxide and soot compared to the experimental data.

• Journal of the Korean Society of Marine Environment & Safety
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• v.11 no.1 s.22
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• pp.53-59
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• 2005

It is very dongerous for ship‘s fire which occurs from navigating because of it will not be able to expect fire fighting from land so that handle with the oneself to control. Additionally, in the case of passenger ship is more serious for the reason of not only the property damage but also large life accident can be occurred continuously. When the fire occurs, the many smoke to occur simultaneously as well as the heat from combustion process and the poisonous smoke is brought the life damage as the death from suffocation The purpose of this study is to examine the smoke movement characteristics in the ship's indoor spaces with fire size and location An experimental study was carried out with two sized of fires and three typed of fire source locations. As the results, the smoke and heat diffusion characteristics Ms been showed the most quick rise curve in the case of comer type fire.

• Proceedings of KOSOMES biannual meeting
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• 2005.05a
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• pp.167-173
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• 2005

It is very dangerous for ship‘s fire which occurs from navigating because of it will not be able to expect fire fighting from land so that handle with the oneself to control. Additionally, in the case of passenger ship is more serious for the reason of not only the properly damage but also large life accident can be occurred continuously. When the fire occurs, the many smoke to occur simultaneously as well as the heat from combustion process and the poisonous smoke is brought the life damage as the death from suffocation. The purpose of this study is to examine the smoke movement characteristics in the ship's indoor spaces with fire size and location An experimental study was carried out with two sized of fires and three typed of fire source locations. As the result of it, the smoke and heat diffusion characteristics has been showed the most quick rise curve in the case of comer type fire.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.11a
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• pp.49-49
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• 2013

실규모급 화재 실험의 신뢰성 있는 발열량 측정을 위해서 흡입 배관의 직경 1.6 m, 직선길이 26m, 후드 직경 10 m 그리고 흡입용량 $2,000m^3/min$ 이상의 대형 콘 칼로리미터를 구성하여 헵탄의 화재 크기별 연소 실험을 진행하였다. 발열량 측정을 비교 분석하기 위해서 산소 소모 지수법, 질량 소모법, 복사열 그리고 대류열 측정 기법에 따라서 각각의 발열량을 산출하고 크기를 비교하였다. 그 결과 대형 콘 칼로리미터에 의해서 측정한 산소 소모 지수법은 이론 발열량에 해당하는 질량 소모법과 최대 약 2.3 % 정도, 복사열에 의한 발열량 산출법은 12.2 % 정도, 연소면적에 의한 이상적인 발열량과는 최대 30 % 정도, 그리고 대류열만 고려한 경우 약 50 % 정도 차이가 나는 것을 확인하였다.

• Fire Science and Engineering
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• v.18 no.2
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• pp.7-11
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• 2004

In this paper, we have simulated the force between the two electrical wires using the finite element method(FEM) according to the value of current and distance when overcurrent flows in the vinyl-insulated vinyl-cabtyre cord(flat-type, 600 V, VCTFK, $2C{\times}1.25mm^2$). And we will present the basic data for the identification of electrical fire by experiment for maximum distance between the two wires according to current and time using large current supply device(Model : EHT_EFAD, Korea) in case of overcurrent.

• Fire Science and Engineering
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• v.32 no.6
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• pp.15-21
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• 2018

This study examined the flow characteristics of fire smoke under pressurized air ventilation conditions by carrying out fire simulations on multi-compartment enclosure, including room, ancillary room and stair case. Fire simulations were conducted for the air-leakage test facility, which was constructed to measure the effective leakage area and aimed to improve the understandings of fire and smoke movement by analyzing the overall behaviors of fire smoke flow and pressure distributions of each compartment. The simulation results showed that the heat release rate of the fires was controlled sensitively by the amount of air supplied by the ventilation system. An analysis of the velocity distributions between the room and ancillary room showed that fire smoke could be leaked to the ancillary room through the upper layer of the door, even under pressurized air supply conditions. From these results, it was confirmed that the fire size and spatial characteristics should be considered for the design and application of a smoke control system by a pressurized air supply.

• Fire Science and Engineering
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• v.22 no.4
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• pp.1-10
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• 2008

In this study, the effects of vent location, outside temperature, wind velocity and fire size on the performance of natural venting of the vertical vent designed according to NFPA 204 standard and fire characteristics were numerically investigated using CFAST. In cases of the Vent located on most upper wall, lower outside temperature and lower wind velocity, vents met the performance criteria of venting. The larger fire size becomes, the more mass flow rate through a vent becomes, but the lower interface height of smoke layer becomes, so that vent didn't meet the performance criteria of venting. It should be noted that a natural vertical vent be designed considering maximum outside temperature and maximum wind velocity and developing a design fire accurately in order to meet the performance criteria of venting.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.11a
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• pp.104-106
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• 2021

도시의 인구 밀집도가 증가함에 따라 도시의 단위 면적당 건물 밀집도 역시 증가하고 있으며, 이에 도시 화재는 대규모 화재로 발전할 가능성이 높다. 도시 내 대규모 화재로 인한 인명 및 경제적인 피해를 최소화하기 위해 시뮬레이션 기반의 화재 대응 방안들이 널리 연구되고 있으며, 최근에는 시뮬레이션에서 효과적인 화재 대응 방안을 탐색하기 위해 강화학습 기술을 활용하는 연구들이 소개되고 있다. 그러나, 시뮬레이션의 규모가 커지는 경우, 상태 정보 및 화재 대응을 위한 행위 공간의 크기가 증가함으로 인해 강화학습의 복잡도가 증가하며, 이에 따라 학습 확장성이 저하되는 문제가 발생한다. 본 논문에서는 시뮬레이션 규모 증가 시 강화학습의 학습 확장성을 유지하기 위해, 화재 상황 정보와 재난 대응을 위한 행위 공간을 변환하는 기법을 제안한다. 실험 결과를 통해 기존에 강화학습 모델의 학습이 어려웠던 대규모 도시 재난시뮬레이션에서 본 기법을 적용한 강화학습 모델은 학습 수행이 가능하였으며, 화재 피해가 없는 상황의 적합도를 100%로 하고, 이것 대비 99.2%의 화재 대응 적합도를 달성했다.

• Fire Science and Engineering
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• v.31 no.6
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• pp.8-15
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• 2017

Most fire victims succumb to smoke inhalation, and fire smoke toxicity from interior materials is increasing with increased use of plastics. Large amounts of hazardous effects of smoke are related to deposition of smoke particles in respiratory tracts, and deposition characteristics are influenced by size distribution of particles. Thus, it is essential to know the size distribution of smoke particles from plastics for hazard analysis of fire smoke. In a recent study, it has been shown that size distributions of smoke particles from PP are different from wood in many aspects. In order to know whether other plastics show the same characteristics as PP, size distributions of smoke particles from four plastic materials (LDPE, PA66, PMMA, and PVC) were measured in real time under each fire type with various temperature and oxygen supply. In this study, smoke particles from different plastics were generated uniformly by using steady-state tube furnace method provided in ISO/TS 19700. Their size distributions were measured by using an electrical low pressure impactor (ELPI). Results of measurements showed that size distributions of smoke particles from these four plastic materials were similar to those from PP in many aspects. However, they were distinctively different from those of wood.