• Title/Summary/Keyword: Combustion Phenomena

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Evaluating Impact Factors of Forest Fire Occurrences in Gangwon Province Using PLS-SEM: A Focus on Drought and Meteorological Factors (PLS-SEM을 이용한 강원도 산불 발생의 영향 요인 평가 : 가뭄 및 기상학적 요인을 중심으로)

  • Yoo, Jiyoung;Han, Jeongwoo;Kim, Dongwoo;Kim, Tae-Woong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.41 no.3
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    • pp.209-217
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    • 2021
  • Although forest fires are more often triggered by artificial causes than by natural causes, the combustion conditions that spread forest fire damage over a large area are affected by natural phenomena. Therefore, using partial least squares structural equation modeling (PLS-SEM), which can analyze the dependent and causal relationships between various factors, this study evaluated the causal relationships and relative influences between forest fire, weather, and drought, taking Gangwon Province as our sample region. The results indicated that the impact of drought on forest fires was 27 % and that of the weather was 38 %. In addition, forest fires in spring accounted for about 60 % of total forest fires. This indicatesthat along with meteorological factors, the autumn and winter droughts in the previous year affected forest fires. In assessing the risk of forest fires, if severe meteorological droughts occur in autumn and winter, the probability of forest fires may increase in the spring of the following year.

A Study on the Prediction of Flashover Time and Heat Release Rate(HRR) for Building Interior Materials (건축 내장재의 Flashover시간 및 열방출량 예측에 관한 연구)

  • 하동명
    • Fire Science and Engineering
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    • v.18 no.3
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    • pp.30-38
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    • 2004
  • An important characteristics during fire growth is the phenomena of flashover, which is the transition from the local combustion to the full-room fire. The aim of this study is to predict the flashover times, the ignition times and HRR(heat release rate) of flashover for building interior materials. By using the literature data and RSM(response surface methodology), the new equations for predicting the flashover time, the ignition time and the HRR of building interior materials are proposed. The A.A.P.E.(average absolute percent error) and the A.A.D.(average absolute deviation) of the reported and the calculated flashover times were 38.74sec and 51.24sec respectively, and the correlation coefficient was 0.975. The A.A.P.E and the A.A.D of the reported and the calculated ignition times were 10.96sec and 1.97sec, and the correlation coefficient was 0.962. Also the A.A.P.E and the A.A.D. of the reported and the calculated the HRR of flashover by means of times were 29.92 and 514, and the correlation coefficient was 0.830. The values calculated by the proposed equations were in good agreement with the literature data. Therefore, it is expected that this proposed equations will support the use of the research for other building interior materials.

The study on Coal Spontaneous Ignition Prevention using Safety Materials of Food and Cosmetics (식품과 화장품의 안전 소재를 이용한 석탄 자연발화 억제에 대한 연구)

  • Jun, Soo-Man;Kim, Young-Hee
    • Journal of the Korean Applied Science and Technology
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    • v.39 no.2
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    • pp.368-376
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    • 2022
  • Spontaneous ignition occurs in industrial sites or anywhere in our lives, and is a phenomenon in which a substance ignites itself without an ignition source in the atmosphere. As the rate of chemical reaction increases, the heat generated increases, and the risk of spontaneous ignition increases. In this study, safe raw materials used for food and cosmetics were mixed to prepare coal spontaneous ignition prevention agents specifically among various spontaneous ignition phenomena. The effect of suppressing spontaneous combustion of coal was confirmed through lab and field tests with low-calorie, low-grade coal from Indonesia. As a result of the outdoor field test, the ignition prevention agent manufactured in this study compared with the control group(Fire after 90 days) showed excellent ignition inhibitors for more than 120 days. In addition, CO concentration control was confirmed by comparing the concentration of carbon monoxide for 50 days at the indoor coal yard. It was confirmed that the results were better than the comparative group coal and the existing anti-firing method. In addition, the possibility of coal fire prevention agents for indoor coal farms will be applied from 2024 was confirmed by studying the environment and safety of workers' working environments through official test such as soil and water quality test, MSDS of coal fire prevention agents in consideration of working workers, water quality, and eye irritation tests.