Effect of Spray Angle of Water Mist Nozzle on Temperature Field of Compartment Fire

물분무노즐의 분사각이 화재실 내부의 온도장에 미치는 영향

  • 김성찬 (중앙대학교 대학원) ;
  • 유홍선 (중앙대학교 기계공학부) ;
  • 박현태 (중앙대학교 대학원) ;
  • 방기영 (중앙대학교 대학원)
  • Published : 2003.06.01

Abstract

The present study investigates the effect of injection angle of water mist on fire suppression characteristics by numerical simulation. In order to validate the temperature field by numerical simulation, the predicted results are compared with experimental data. It shows that the temperature difference between measurements and predictions are within $10^{\circ}C$. Numerical simulations of fire suppression are performed for 4 different injection angle($60^{\circ}$, $90^{\circ}$, $^120{\circ}$, and $180^{\circ}$). The global mean temperature over the fire compartment decrease with increasing of spray angle. The result shows that the heat transfer between droplets and gas phase are enhanced with the increasing of spray angle. Near the fire source, temperature field by the wide spray angle is slightly higher than that of narrow injection angle because of direct cooling of fire source.

Keywords

fire suppression;water mist;spray angle;numerical simulation

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