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Evaporation Cooling Phenomena of Droplets Containing Fire Suppression Agents (화제 억제제가 첨가된 수용액 액적의 증발냉각 현상)

  • 유갑종;방창훈;김현우
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.9
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    • pp.895-903
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    • 2001
  • Evaporation cooling phenomena of droplets containing fire suppression agents on a hot metal surface were experimentally investigated. Solution of water containing potassium acetate (30-50% by weight) and sodium bromide (10-30% by weight) were used in the experiments, and surface temperatures were ranged from 70-116$^{\circ}C$. The evaporation time of the droplet on the heated surface was determined by using frame-by-frame analysis of the video records. It is found that the apparent evaporation time is shorter in turns of pure water, sodium bromide solution and potassium acetate solution. However, the time averaged heat flux is higher in turns of pure water, sodium bromide solution and potassium acetate solution. In-depth temperature variation of the hot metal does not occur significantly by the kinds of additive.

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A Study on the Cooling Effect of a Water Fire Extinguishing Agent Containing NaBr (NaBr을 첨가한 물소화제의 냉각효과에 관한 연구)

  • 방창훈;김종석
    • Fire Science and Engineering
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    • v.15 no.2
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    • pp.6-12
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    • 2001
  • The objective of the present work is to examine the cooling effect of a water fire extinguishing agent containing NaBr(30%, w/w). The carbon steel and teflon were used as a hot solid. The temperature on the hot solid surface ranged from $70^{\circ}c$ to $116^{\circ}c$ and water droplet size was 2.6 mm in the experiments. It is suggested that regardless of the hot solid material, the indepth temperature of the case of NaBr solution is lower than that of pure water and the variation of indepth temperature of teflon is higher than that of carbon steel. Regardless of the hot solid material, the time averaged heat flux of the case of pure water is higher than that of NaBr solution. the apparent evaporation time of the case of pure water is shorter than that of NaBr solution.

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