• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.8
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• pp.2030-2038
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• 1995

In this study, three turbulent flame propagation models are compared using experimentally measured data of a 4 valves/cylinder spark-ignition engine. First two conventional models are B.K model and GESIM combustion model. The burning rates calculated from the two models are compared with the burning rates calculated from measured pressure data using the one-zone heat release analysis. GESIM combustion model predicts burning rates closer to the data acquired from the experiment in wide operating ranges than B-K model does. The third model is refined based on GESIM combustion model by including the effect of flame stretch, turbulent length scale band pass filter and a variable that considers flame size and the area of flame contacting the cylinder wall surface. The refined combustion model predicts burning rates closer to experimental results than GESIM combustion model does. Also, the refined combustion model predicts flame radius close to the experimental result measured by using optical fiber technique.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.10
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• pp.2787-2796
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• 1994

The modeling of combustion process is an important part in an engine simulation program. In this study, calculated results using a conventional B-K model and the other model which is called GESIM were compared with experimentally measured data of a three-cylinder spark-ignition engine under wide range of operating conditions. The burn rates calculated from the combustion models were compared with the burn rate calculated from the one-zone heat release analysis that uses measured pressure data as an input data. As a result of the two models' comparison, the GESIM combustion model conformed to be closer to the data acquired from the experiment in wide operating ranges. The GESIM model has been improved by introducing a variable that considers the flame size, the area of flame conacting the piston surface into the model, based on the comparison between the experimental result and the calculated results. The improved combustion model predicts experimental results more precisely than that of GESIM combustion model.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.249-252
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• 2012

Experiments have been conducted to clarify flame spread behavior over electrical wire near the end of wire with applied AC electric fields. It is seen that the flame spread behavior near the end of wire with applied AC electric fields are quite different from that in temporally linearly-increasing flame position. The flame spread behavior can be categorized into three regimes based on the relevance of flame shape and the slanted direction of spread flame to spread rate. Detailed explanations on the characteristics are made through thermal balance mechanism. Also, the effect of drop of molten PE and fuel vapor-jet in flame spread is also discussed.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.04a
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• pp.178-178
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• 2013

본 연구는 산림 내 주요 시설물 주변의 소나무, 리기다소나무, 해송, 잣나무, 굴참나무낙엽 5종 및 소나무광솔 등 주요 산불연료에 대하여 연소특성을 분석하고자 착화특성과 전파특성을 실험 한 결과, 발화온도의 경우 소나무낙엽($285^{\circ}C$)이 가장 낮게 측정되어 발화위험성이 가장 높은 것으로 나타났으며, 착화시간의 경우 굴참나무낙엽(발화온도 $305^{\circ}C$)이 3초로 가장 빠르게 나타났고, 화염유지시간의 경우 굴참나무낙엽이 가장 긴 것으로 나타났다. 또한, 전파특성 실험결과 소나무 광솔이 총열방출량 $72MJ/m_2$, 평균열방출율 $40KW/m_2$, 최대열방출량 $206KW/m_2$로 가장 높았으며, 두번째는 소나무낙엽으로 나타났다. 따라서, 실제 산불에서도 소나무광솔과 소나무낙엽이 화염전파에 더 영향을 줄 것으로 사료되었고, 또한, 연료별 탄소배출량 분석 결과 평균$CO_2$방출량이 가장 큰 수종은 리기다소나무낙엽(1.33kg/kg)이며, 평균CO방출량이 가장 큰 수종은 굴참나무 낙엽(0.075kg/kg)으로 나타났다.

• 한국가스학회:학술대회논문집
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• 2007.04a
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• pp.166-169
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• 2007

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.05a
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• pp.419-424
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• 2002

주방연소기의 사용 부주의로 인한 화재는 일반주택 및 다량의 열원을 사용하는 음식점 등에서 발생가능성이 가장 높다. 한편, 화재발생으로 인한 사망자의 80％는 연소가스에 의한 질식으로 사망하게 된다. 주방에 설치된 연소기 상부에는 일반적으로 배열, 제습 및 그리스제거 목적으로 주방후드를 설치되고 있으나 화재를 대비한 복합기능설비로 고안되어 있지 않다.(중략)

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.305-306
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• 2015

• Journal of the Korean Institute of Gas
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• v.12 no.3
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• pp.68-74
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• 2008

Measurements were performed to investigate the effects on flame and pressure development by varying locations of multiple obstacles in a top-venting explosion chamber. The chamber dimension was 1000 mm in height with a $700\;{\times}\;700\;mm^2$ cross-section and a rectangular vent area of $700\;{\times}\;700\;mm^2$. Three different multiple obstacles with blockage ratio of 30% were used by changing from 200 mm, 500 mm to 800 mm in heights within the chamber. Temporally resolved flame front images were recorded by a high speed camera to investigate the interaction between the propagating flame and the obstacles. The results showed that the triangular bar caused the fastest flame developments at given times whereas the lowest was obtained with the cylindrical bar. It was also found that local flame displacement speeds of different obstacles were sensitive to the locations of obstacles. The local speed becomes larger in going from 200 mm, to 500 mm and to 800 mm in heights. The obstacles in height of 800 mm yielded the highest overpressure whereas the lowest was in height of 200 mm.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.04a
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• pp.402-407
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• 2011

최근 친환경 자재를 사용한 건축물이 증가하면서 전통 가옥 뿐만 아니라 다양한 형태의 목조 건축물들이 많이 지어지고 있다. 목재는 건축자재로서 우수한 장점이 많은 반면 화재에 취약한 치명적인 단점을 갖고 있다. 본 연구는 목재건축물의 화재특성을 분석하기 위하여 목재건축물의 화재해석 모델링을 구성하고 수치해석하였으며, 화재시 화염전파의 패턴을 분석하였다. 발화는 내부발화와 외부 화염전이로 구분하였으며 내부발화는 다시 건물 중앙 발화와 벽면발화로 구분하여 수치해석을 수행하였다.

• Fire Science and Engineering
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• v.26 no.1
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• pp.31-37
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• 2012

This study is intended to present a computational thermal model for a residential building. As the Performance Based Design is more popular, fire-intensity and fire-load have turned out to be very important factors for building design and can be predicted through some computational work. To predict and estimate the fire properties of a residential fire, we made some numerical models of combustibles and residential building. In a bid to validate the estimate values, computational analysis results from numerical models were compared with real fire tests. For computational analysis, the Fire Dynamics Simulator (FDS) was used with Large Eddy Simulation (LES) model for turbulence. Consequently, fire-intensity was well predicted and flash-over of rooms were successfully estimated.