• 한국안전학회지
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• 제30권4호
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• pp.32-38
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• 2015

In this paper, we analyzed the vehicle fire accidents due to damage of vehicle's electrical components, which is applied to a vehicle. In recent development of electrical components technology, approximately 40% of vehicle manufacturing parts have applied electronic circuit technology. Phenomenon such deterioration of insulating performance or electric breakdown on the vehicle's electrical components and printed circuit boards(PCBs) resulted from moisture, contamination and aging due to repetitive operations, lead to the vehicle fire. Therefore, the application of electrical components with adequate electric capacity for vehicle and usage of molding techniques using a non-combustible materials to shut off the oxygen should be applied in order to prevent vehicle fire due to damage of the electrical components and PCBs.

• 한국안전학회지
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• 제23권3호
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• pp.36-41
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• 2008

For the safety design and operation of many chemical process, it is necessary to know certain explosion limit, flash point and autoignition temperature(AIT) of handling substances. Also it is necessary to know explosion limit at high temperature and pressure. For the safe handling of MEK(methyl ethyl ketone), explosion limit at $25^{\circ}C$ and the temperature dependence of the explosion limits were investigated. And flash point and AIT for MEK were experimented. By using the literatures data, the lower and upper explosion limits of MEK recommended 1.8 vol% and 11.0 vol%, respectively. In this study, measured the lower and upper flash points of MEK were $-5^{\circ}C$ and $22^{\circ}C$, respectively. This study measured relationship between the AITs and the ignition delay times by using ASTM E659-78 apparatus for MEK, and the experimental AIT of MEK was $507^{\circ}C$. The new equations for predicting the temperature dependence of the explosion limits of MEK is proposed. The values calculated by the proposed equations were a good agreement with the literature data.

• 환경위생공학
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• 제13권3호
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• pp.9-18
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• 1998

An experimental research was conducted to establish primary data for the stabilization assessment of industrial wastes landfill with analysis of waste components and investigation of leachate and gas generation, using three sets of lysimeter as experimental apparatus. Comparing results of lysimeter from data of landfill, it is suggested that lysimeter of this study can be used to accomplish the stabilization assessment of the real landfill site. Moisture content was lower as landfill period was older and combustible component was the highest in lysimeter C. The C/N ratio of waste was 7.4~14.4 and, with the elemental analysis, the theoretical gas generation rate based on the modified Buswell equation was 0.47~0.49 $m^3/kg-dry$ waste in lysimeter C. Considering the C/N ratio of leachate, it is concluded that the addition of carbon source is needed to biodegrade leachate hereafter. Gas generation rate($m^3/kg-dry$ waste) from lysimeter A, B and C was 0.0009, 0.014 and 0.0067, respectively, and different from each other according to the landfill period of wastes. The results in this study show that the biodegradation of microorganism for stabilization of landfill was inhibited and more activated in acidogenic step than in methanogenic of anaerobic degradation.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.92.1-92.1
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• 2011

Anode off-gas of high temperature fuel cells such as MCFC contains a significant amount of combustible components like hydrogen, carbon monoxide and methane according to fuel utilization ratio of the fuel cell stack. Thus, it is important to fully burn anode off-gas and utilize the generated heat in order to increase system efficiency and reduce emissions as well. In the present study, 25 kW catalytic combustor has been developed for the application to a load-following 300kW MCFC system. Mixing and combustion characteristics have been experimentally investigated with the catalytic combustor. Since the performance of catalytic combustor directly depends on the combustion catalyst, this study has been focused on the experimental investigation on the combustion characteristics of multiple catalysts having different structures and compositions. Results show that the exhaust emissions are highly dependent on the catalyst loading and the ratio of catalytic components. Test results at load-following conditions are also shown in the present study.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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• pp.369-374
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• 2010

본 연구에서는 가스 연료와 공기 혼합물 내 압력파에 의해 유도되는 화염 가속과 연소폭발천이 현상을 수치적 계산을 통하여 살펴본다. 실험에 기반을 둔 초기 조건 하에서 점성력, 열전단, 몰질량 확산, 그리고 화학 반응을 고려한 reactive compressible Navier-Stokes 방정식을 사용하여 계산을 수행하였다. 반복되는 압력파와 화염의 상호 작용에 의해 발생되는 화염의 Richtmyer-Meshkov (RM) 불안정성에 의해 증가된 화염면을 통하여 생기는 hot spot들에 의한 폭굉의 발생을 모델링하였다. 또한 압력파의 강도 변화에 따른 연소폭발천이 현상의 변화를 살펴보았다.

• 한국화재소방학회논문지
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• 제25권2호
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• pp.120-125
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• 2011

노말도데칸의 안전한 취급을 위해서 25에서 폭발한계를 고찰하였고, 하부인화점과 발화지연시간에 의한 발화온도를 측정하였다. 공정의 안전을 위해서 노말도데칸의 폭발하한계는 0.60Vol.%, 상한계는 4.7Vol.%를 추천하였고, 하부인화점은 밀폐계에서 $77^{\circ}C$과 $80^{\circ}C$와 개방식에서 $84{\sim}87^{\circ}C$로 측정되었다. ASTM E659-78 장치를 사용하여 자연발화온도와 발화지연시간을 측정하였고, 최소자연발화온도는 $222^{\circ}C$ 측정되었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.102-103
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• 2021

In Korea, starting with the Busan residential-commercial fire in 2010, the frequency of fire expansion in high-rise buildings has been continuously increasing. In the case of such large-scale fires, most of the fires generated from the inside tend to expand to the upper floors by riding the exterior material or exterior wall panels through the process of being ejected to the outside. It has been revised so that combustible exterior materials cannot be used in buildings. However, due to the legal fluoride level, the fire risk of high-rise buildings is still high, such as the case of a 33-story residential-commercial fire in Ulsan. In order to prevent such fire expansion, it is considered that it is necessary to first understand the nature of the fire occurring inside and the mechanism of the fire expansion in the upper floor. The purpose of this study is to propose improvements in domestic fire safety design through a review of existing literature to prevent fire expansion of high-rise buildings.

• 한국화재소방학회논문지
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• 제28권4호
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• pp.14-20
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• 2014

본 연구는 인화성 액체를 특정 용기에 담유하고 구획된 공간에서 연소 실험을 실시하여 연소 패턴을 분석하는 데 있다. 담유 실험에 사용된 용기는 깊이 20 mm, 넓이 150 mm의 플라스틱이다. 화염이 착화되어 연소되는 과정은 디지털카메라(digital camera) 및 비디오카메라(video camera)를 이용하여 확보하였다. 화염이 최성기에 도달하는 속도는 벤젠이 가장 빠르고 약 60 s이다. 반면 가장 늦게 것은 알코올이었으며 약 360.0 s로 6배 정도 차이가 있었다. 화염이 최성기에 도달하였을 때 플라스틱 용기와 인화성 액체가 동시에 연소됨에 따라 연기는 대부분 검정색이었다. 연소가 완료된 후유증 검지관(crime investigation tube)을 이용하여 유증을 조사한 결과 대두유를 제외한 모든 인화성 물질에서 유증 채취가 가능했다. 즉, 연소 물질의 종류에 따라 화재의 확산 속도 및 패턴 등에 큰 차이가 있다는 것을 알 수 있었다.

• 한국화재소방학회논문지
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• 제32권2호
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• pp.82-91
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• 2018

고양종합터미널 건물 화재 조사 결과를 토대로 스크린방화셔터의 작동실태 및 문제점 등에 대해 분석하였다. 공사 중이던 지하 1층 공간의 스크린방화셔터는 전원을 차단하여서 작동할 수 없었다. 1층과 3층의 스크린방화셔터는 전원을 차단하지 않았음에도 4개가 작동하지 않았다. 그리고 스크린방화셔터와 관련된 문제점으로 면적별 방화구획을 변경하는 공사를 함에도 층별 방화구획용 스크린방화셔터 전원 차단, 아무런 규제 없이 일체형스크린방화셔터 설치, 피난장애와 관련이 없는 곳에도 2단 스크린방화셔터 설치, 가연성 샌드위치패널로 칸막이 후 층별 방화구획용 스크린방화셔터 기능 정지, 성능이 검증되지 않은 폭 10 m 이상의 스크린방화셔터 설치, 방화셔터 이설 또는 정비 시 안전관리 기준이 없음 등으로 분석하였다.

• Korean Chemical Engineering Research
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• 제56권6호
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• pp.811-818
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• 2018

A fire and explosion accident caused by a liquefied petroleum gas (LPG) welding and cutting torch gas leak occurred 10 m underground at the site of reinforcement work for bridge columns, killing four people and seriously injuring ten. We conducted a comprehensive investigation into the accident to identify the fundamental causes of the explosion by analyzing the structure of the construction site and the properties of propane, which was the main component of LPG welding and cutting work used at the site. The range between the lower and upper explosion limits of leaking LPG for welding and cutting work was examined using Le Chatelier's formula; the behavior of LPG concentration change, which included dispersion and concentration change, was analyzed using the fire dynamic simulator (FDS). We concluded that the primary cause of the accident was combustible LPG that leaked from a welding and cutting torch and formed a explosion range between the lower and upper limits. When the LPG contacted the flame of the welding and cutting torch, LPG explosion occurred. The LPG explosion power calculation was verified by the blast effect computation program developed by the Department of Defense Explosive Safety Board (DDESB). According to the fire simulation results, we concluded that the welding and cutting torch LPG leak caused the gas explosion. This study is useful for safety management to prevent accidents caused by LPG welding and cutting work at construction sites.