• Title/Summary/Keyword: Flux weakening

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The Performance of the Combined Operation of Sprinkler and Smoke Curtain for Smoke Control in the Sloped Stairway Corridor (경사통로로 전파되는 연기에 대한 스프링클러와 제연커텐의 통합제연성능)

  • Jeon, Heung-Kyun;Choi, Young-Sang;Choo, Hong-Lok
    • Fire Science and Engineering
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    • v.20 no.4 s.64
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    • pp.1-12
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    • 2006
  • In this study, CFD computer simulations by FDS are carried out in order to confirm the performance of the combined operation of both sprinkler system and smoke curtain of 0.54 m depth installed for cooling and blocking the smoke which propagates beneath the sloped ceiling of a stairway corridor of which dimensions are 17.92 m long, 4.00 m wide, and 6.12 m high. It is shown that the response time of sprinklers decreases with fire size and it increases more about 1.1 second in case without smoke curtain than in case with smoke curtain, that the time of smoke transport from the fire source to the stairway outlet decreases considerably with fire size, and that the delay effect of smoke transport is not related to the sprinkler system, whether it is operated or not. This study shows that the combined operation of both sprinkler system and smoke curtain is very effective in smoke cooling, but it is a little for effect on smoke blockage. Although the hazard of skin burn due to radiative heat flux from hot smoke layer is decreased by spray cooling effect, the hazard of smoke suffocation and the weakening of visibility is increased by smoke downdrag and the turbulence of smoke-air mixing due to water spray. These conditions may result in preventing occupants from going out of the stairway during evacuation.