• Title/Summary/Keyword: 열 복사

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A Combustion Characteristic Analysis of Sandwich Panel Core Using Radiation Heat Flux (복사열을 이용한 샌드위치 패널 심재의 연소특성 분석)

  • Park, Hyung-Ju
    • Fire Science and Engineering
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    • v.21 no.4
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    • pp.25-31
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    • 2007
  • The combustion characteristics and combustion heat of sandwich panel cores were analysed using variable external irradiation level. The characteristics such as ignition time, critical heat flux, ignition temperature and surface temperature profile were measured. Fuel samples were exposed to incident heat fluxes from 15 to $50\;kW/m^2$. For the measurement of various combustion characteristics, the size of specimen was $100\;mm\;{\times}\;100\;mm\;{\times}\;50\;mm$ and the samples were 3 different kinds. As results, Type B showed the best characteristics in measurement of combustion heat and ignition temperature and Type C showd the best characteristics in critical heat flux and surface temperature profile than that of the other two. In conclusion, we knew that Type C had the best performance in fire safety from all data of this study.

The Hazard Assessment of Release and Dispersion of CNG Service Station (CNG 충전소의 누출$\cdot$확산에 대한 위험성 평가)

  • Choi Jong-Woon;Lee Su-Kyung
    • Journal of the Korean Institute of Gas
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    • v.4 no.3 s.11
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    • pp.53-58
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    • 2000
  • It was carried out consequence analysis(CA) of CNG (compressed natural gas) service station and we compared the results of CA of CNG service station with LPG service station which was installed by high Pressure gas law. The results of CA were that distance of CNG LFL was 1.5 times than the length of LPG LFL. Thermal radiation effect about CNG may not be showed damage of process facilities, but in the case of LPG, it was enough to have an large damage effect on a downtown. The thermal radiation of 37.5 $kw/m^2$ extended 12.6 m. Also, in the case of 12.5 $kw/m^2$ which was able to burn wood, the radiation effect of LPG is 3 times than CNG.

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A Numerical Study of Smoke Movement with Radiation in Atrium Fires (아트리움에서 화재 발생시 복사가 고려된 연기거동에 대한 수치해석 연구)

  • 정진용;유홍선;홍기배
    • Fire Science and Engineering
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    • v.15 no.1
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    • pp.7-15
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    • 2001
  • This paper describes the smoke filling process of a fire field model based on a self-developed SMEP (Smoke Movement Estimating Program) codo to the simulation of fire induced flows in the atrium space (SIVANS atrium at Japan) containing smoke radiation effect. The SMEP using PISO algorithm solves conservation equations for mass, momentum, energy and species, together with those for the modified k-$\varepsilon$ turbulence model with buoyancy term. Also it solves the radiation equation using the discrete ordinates method. The result of the calculated smoke temperature containing radiation effect has shown a better prediction than the result calculated by only convection effect in comparison with the experimental data. This seems to come from the radiation effect of $H_2$O and $CO_2$ gas under smoke productions. Thus, the consideration of the radiation effect under smoke in fire should be necessary in order to get more realistic result. Also the numerical results indicated that the smoke layer is developing at a rate of about 0.1 m/s. It would take about 450 seconds after starting the ultra fast fire of 560 kW that the smoke layer move down to 1.5m above the escape level.

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