• 제목/요약/키워드: fire growth

검색결과 350건 처리시간 0.038초

FDS를 이용한 실내화재 모사의 문제점 II. 벽면형 및 모서리형 화재 (A Numerical Study of a Room Fire for Fire Sizes II. wall fire and corner fire)

  • 고경찬;박외철
    • 한국안전학회지
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    • 제19권3호
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    • pp.9-13
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    • 2004
  • To confirm the previous finding that FDS predicts a fire growth rate too rapid compared with an experiment in a center fire in a room with an opening, the same computational fluid dynamics was applied to two types of fires, wall fire and comer fire. First the grid size was chosen to eliminate possible numerical errors due to a coarse grid system. Then the two types of fires were simulated for three different fire sizes, 7.65, 21.25, and 51.57kW for each type, which are the same as in the experiment to be compared with. The fires were predicted to grow too fist although the average temperatures and heights of the neutral planes were in good agreement with measurement.

붕소/실리콘 졸 화합물로 도포된 편백 목재의 연기유해성 평가 (Smoke Hazard Assessment of Cypress Wood Coated with Boron/Silicon Sol Compounds)

  • 진의;정영진
    • 한국화재소방학회논문지
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    • 제34권1호
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    • pp.1-10
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    • 2020
  • 본 연구는 건축 및 내구재용 목재인 편백 목재에 붕소/실리콘 졸 화합물을 처리한 후 화재위험성을 연기 유해성에 대하여 연기성능지수(SPI), 연기성장지수(SGI)와 연기강도(SI)를 중심으로 조사하였다. 화합물은 Tetraethoxyorthosilicate를 Boronic acid와 Boric acid 유도체와 반응시켜 합성하였다. 연기 특성은 편백목재에 대하여 Cone calorimeter (ISO 5660-1) 장비를 이용하여 조사하였다. 화재강도는 50 kW/㎡의 외부 열 유속(External heat flux)으로 고정시켰다. 연소 반응 후 측정된 연기성능지수는 편백목재와 비교하여 13.4~126.7% 증가하였다. 연기성능지수에 의한 화재위험성은 편백목재, PBA/Si, IBBA/Si, BA/Si 순서로 감소하였다. 연기성장지수는 편백목재와 비교하여 12.0~57.5% 감소하였다. 연기성장지수에 의한 화재위험성은 편백목재, PBA/Si, IBBA/Si, BA/Si 순서로 낮아졌다. 연기강도에 의한 화재위험성은 3.2~57.8% 감소하였으며 편백목재, PBA/Si, IBBA/Si, BA/Si 순서로 낮아졌다. COpeak 농도는 85~93 ppm였으며 공시편과 비교하여 37~43% 감소하였다. 화재위험성을 연기유해성에 대해 종합적으로 평가하면 편백목재, PBA/Si, IBBA/Si, BA/Si순서로 낮아졌다.

구획실 내 가연물들의 화재거동에 대한 B-RISK와 FDS 연계 화재 시뮬레이션 예측성능 평가 (Evaluation of the Prediction of B-RISK-FDS-Coupled Simulations for Multi-Combustible Fire Behavior in a Compartment)

  • 백빛나;오창보
    • 한국화재소방학회논문지
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    • 제33권4호
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    • pp.50-58
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    • 2019
  • 구획실 내 가연물들의 화재거동에 대한 B-RISK의 예측성능을 Fire dynamics simulator (FDS)와 연계하여 검토하였다. 먼저 열발생률(Heat release rate, HRR)에 대한 B-RISK의 예측성능을 검토하기 위해 가연물 한 세트의 실험에서 측정된 HRR 값과 디자인 화재곡선을 B-RISK의 입력조건으로 사용하여 가연물 두 세트에 대한 HRR 곡선을 계산하고 실험에서 측정된 가연물 두 세트의 HRR 값과 비교하였다. B-RISK 결과와 실험결과를 비교하여 B-RISK가 화재성장률에 대한 예측은 어렵지만 최대 HRR 값과 총 열발생량에 대해서는 충분히 예측할 수 있음을 확인하였다. 그리고 B-RISK 계산을 통해 예측된 HRR 값을 FDS의 입력조건으로 사용하여 계산된 결과와 실험결과를 비교하여 B-RISK 계산을 통해 예측된 HRR 값의 화재거동에 대해 검토하였다. 실험에서 측정된 온도 및 화학종 농도 결과와 비교하여 화재성장구간에 대해 차이가 있는 것을 확인하였지만 예측된 HRR 값에서 Percentile이 약 70%인 HRR 값을 사용하더라도 충분히 전체적인 화재거동을 예측할 수 있음을 확인하였다.

경년열화 기간에 따른 원자력발전소용 비안전등급 케이블의 연소특성 분석 (Combustion Characteristics Analysis of a Non-class 1E Cable for Nuclear Power Plants according to Aging Period)

  • 김민호;이석희;이민철;이상규;이주은
    • 한국안전학회지
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    • 제35권5호
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    • pp.22-29
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    • 2020
  • In this study, combustion and smoke release characteristics of a non-class 1E cable for nuclear power plants were investigated according to aging period. The aging was reproduced through an accelerated aging method for interval of 10 years :10, 20, 30 and 40 year, which was applied the Arrhenius equation. The cable was subjected to accelerated aging. In order to understand combustion and smoke release characteristics, the cone calorimeter test was performed according to the standard code of KS F ISO 5660-1. Heat release rate, mass loss rate, average rate of heat emission and smoke production rate were examined through cone calorimeter test. Fire performance index, fire growth index and smoke factor were derived from test results for the comparison of quantitative fire risk. When comparing the fire performance index and the fire growth index, the early fire risk tends to decrease as aging progresses, which might be attributed from the fact that the volatile substances of cables were evaporated. However, when comparing the heat release rate, average rate of heat emission and mass loss rate, which represent the mid and late periods of the fire risk, the values of accelerated aging cables were much higher than those of non-aged cable, which signifies the unstable formation of the char layer resulted in the change in the performance of flame retardants. In addition, the results from the smoke characteristics show that the accelerated aging cables were lager than the non-aged cables in terms of overall fire risk. These results can be used as baseline data when assessing fire risk of cables and establishing fire safety code for nuclear power plants.

불임(不姙)과 생활습관의 상관성에 대한 연구 (Study on the influence of life-style on infertility)

  • 방정균
    • 한국의사학회지
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    • 제18권1호
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    • pp.3-14
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    • 2005
  • Among modern people's life-style, the lack of exercise and sleep is related to infertility. Underexercise accumulates damp-sputum, resulting in the insufficiency of essence. It also obstructs the creation of essence, leading to insufficient essence. Activities at night without sleep cannot create the condition to help the process of yin, causing the insufficiency of essence. Fast food is made from the cattle which are fed the feed containing growth hormone and antibiotics in large quantities. Growth hormone causes the process of yang excessively in human body, while antibiotic suppresses the process of yin, leading to excessive damp-heat and hyperactive ministerial fire. Antiseptic included in instant food hampers the process of fermentation, or yin, and inhibits the digestion mechanism, obstructing damp-heat and bringing about hyperactive ministerial fire. Intake of excessive flesh and meat gives rise to incomplete combustion and hinders the creation of essence, causing hyperactive ministerial fire due to the lack of yin. Milk suits the calf that has a rapid growth cycle. Milk intake by humans leads to the rapid process of yang and eventually hyperactivity of ministerial fire. The imbalance between yin and yang, with essence insufficent and ministerial fire hyperactive, causes infertility in three aspects. First, the lack of essence itself makes conception difficult. Secondly, damp-sputum resulting from ministerial fire obstructs the circulation of qi and blood. It also hampers the normal supply of qi and blood to the uterus. Thirdly, the excessive process of yang may result in infertility. Generally speaking, pregnancy starts with implantation. If the excessive process of yang is in progress in body, static condition needed for implantation cannot be maintained, leading to infertility.

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화재 Simulation에서의 Field Model (A Review on The Field Model for Fire Simulation)

  • 김진곤
    • 한국화재소방학회논문지
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    • 제8권1호
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    • pp.26-33
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    • 1994
  • The review of field model for fire simulation is presented. The approach to predict ire growth by solving the conservation equations over time and 2- or 3-dimentional space with appropriate boundary conditions is called field model. The finite difference method is adopted to solve the governing equations. The results is give qualititively and quantitatively good results but complicate and difficult to handle. But it is useful tool to understand detail phenomenons and to make decision for fire safety.

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FIRE PROTECTION FOR PETROCHEMICAL PLANT

  • Suh, Jung-H.
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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    • pp.244-251
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    • 1997
  • Since 1970s, The Petrochemical Industry in Korea has grown rapidly by the successful economic growth. While the process became larger and more complex, hazardous chemicals have been used in large quantity, Therefore, the risk of a major accident such as fire, explosion and toxic material release has been increased. Korea has been ranked the fifth in petrochemical product capacity worldwide, also required to meet international standards on process safety management. Fire Protection System integral part of safely management in Petrochemical Plants, will be reviewed.

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단일화재실험을 통한 화재성상예측 및 건축구조물의 화재안전 설계에 관한 연구 (A Study on the Fire Safety Design and Predicting Fire Behavior Using Compartment Fire Test)

  • 윤웅기;서동구;김동은;권영진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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    • pp.107-108
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    • 2013
  • In this study, combustibles investigation and fire growth rate experiment were performed for predicting initial fire behavior in buildings. Combustibles investigation was performed for residential buildings, which is most frequently affected by fire in Korea. Spatial characteristics and combustibles properties were separately investigated, and occupied area and layout characteristics of combustibles were identified to produce general layout models. Of the layout models, room was selected for fire test of a single compartment. From this test, fire propagation for each combustible was identified, which was delayed compared to the summed heat release rate of a single combustible.

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