• 한국화재소방학회논문지
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• 제9권2호
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• pp.10-16
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• 1995

This study discribes characteristics of water spray for extinguishment of gasoline fire. Experiments are carried out for the gasoline pool fire nth the atomizing nozzles. Droplet size, spray pressure, amount of water which reaches the flame base and velocity of water spray are measured to find extinguishment conditions. Air entrainment due to the water spray and extinguishing process of gasoline fire by water spray are visualized. Boundary conditions of water spray for extinguishment of gasoline pool fire is quantitatively shown. As the result of experiments, it is found that the velocity of entrainment air and sprayed water are almost same and the water droplets size having small diameter under 40$\mu\textrm{m}$ can not extinguish the fire because too small droplets does not reach the fuel surface.

• 한국산업융합학회 논문집
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• 제26권5호
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• pp.907-913
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• 2023

Currently, the sprinkler method is widely used as an initial suppression method in existing firefighting systems. However, this method can cause significant damage to both equipment and facilities in the hydration area. To minimize this damage, fire extinguishing monitors are being developed that can spray fire extinguishing water directly at the point of fire. These monitors are installed on the top floor of the ship, such as the Living Quarter and Ventilation System. While conventional fire extinguishing monitors focus on lightweight research with a short spray port and require a spray distance of about 40 to 45m, recent developments necessitate a longer spray port, similar to a water cannon, requiring a spray distance of about 70 to 75m. This study aims to predict the injection distance of both the existing ship-installed fire extinguisher and the long spray port fire extinguisher through hydrodynamic computer analysis, and to determine whether the injection distance has increased.

• 연구논문집
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• 통권25호
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• pp.129-135
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• 1995

This study discribes characteristics of water spray for extinguishment of gasoline pool fire. Experiments are carried out for the gasoline pool fire in a small tank with a diameter of 150mm and a height of 8mm. Droplet size, spray pressure, amount of water which reaches the flame base and velocity of water spray are measured to find extinguishment conditions and air entrainment due to the water spray is visualized. Critical conditions of water spray for extinguishment of gasoline pool fire is quantitatively shown.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.218-221
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• 2008

The real scale fire suppression test inside a road tunnel were carried out for water spray systems. The dimension of the tunnel is 7.5m in height and 11.6m in width. 3 different water spray nozzle systems with low operating pressure less than 3.5 bar were used in the experiment. Two types of fires were tested. One is a $1.4m^2$ heptane pool fire and the other is a 2000CC passenger car fire. From the experiment, the spray densities of tested systems were about $6.0\;l/min/m^2$ which is currunt domestic guideline. Although all the systems cannot extinguish the tested fires, it was found that they can reduce the tunnel temperature and have a capability to control and suppress the tested fire.

• 한국분무공학회지
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• 제22권4호
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• pp.175-184
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• 2017

The numerical investigation on the effects of water-mist characteristics has been carried out for the fire suppression mechanism. The FDS are used to simulate the interaction of fire plume and water mists, and program describes the fire-driven flows using LES turbulence model, the mixture fraction combustion model, the finite volume method of radiation transport for a non-scattering gray gas, and conjugate heat transfer between wall and gas flow. The numerical model is consisted of a rectangular enclosure of $L{\times}W{\times}H=1.5{\times}1.5{\times}2.0m^3$ and a water mist nozzle that be installed 1.8 m from fire pool. In the present study, the parameters of nozzle for simulation are the droplet size and the spray velocity. The droplet size influences to fire flume on fire suppression more than the spray velocity because of the effect of the terminal velocity. The optimal condition for fire suppression is that the droplet size and the spray velocity are $100{\mu}m$ and 20 m/s respectively.

• 한국터널지하공간학회 논문집
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• 제12권4호
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• pp.341-347
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• 2010

터널화재 시 위험을 경감시키기 위해 설치하는 물분무설비의 성능을 실대 시험을 통해 확인하였다. A급 화재, Pool 화재 및 차량화재시 물분무노즐은 뜨거운 연기의 온도를 낮추는데 효과가 큰 것으로 확인되었다. 또한 터널에 기류가 존재하는 경우에도 냉각효과가 큰 것으로 확인되었다. 이 결과를 통해 물분무설비는 터널화재 시 기류온도를 낮춤으로써 fire jump를 방지하고, 주위의 시설물을 보호할 수 있을 것으로 판단된다.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.200-203
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• 2008

Water mist fire suppression system utilizes the fire suppression features such as cooling of fire source, dilution of ambient oxygen, and shielding of radiation heat with the evaporation of microscopic water droplets. The momentum of water mist is relatively low and the infiltration of water mist to the fire source is not effective. In addition to lower penetration force, the evaporated water vapor is liable to decline to limited portion of fire source due to its light weight and sparse density. On the other hand, the cycling water mist system is expected to improve the penetration force of water mist as well as the dilution coverage capability with the stratified spray characteristics. At this paper we present the analyzed fire suppression capability of intermittent water spray pattern by use of FDS which is computational fire dynamics fire model. We expect this analysis shall be supportive to the development of the prototype of water mist nozzle.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1703-1708
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• 2003

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 grobal 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 enhaced 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.

• 한국안전학회지
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• 제18권2호
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• pp.28-33
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• 2003

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.

• 대한기계학회논문집B
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• 제29권1호
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• pp.151-158
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• 2005

A characteristic of discharge for a foam spray nozzle with various parameters was investigated. The discharge patterns from a fire foam spray nozzle are important to evenly spray over a maximum possible floor area. Two parameters of a foam spray nozzle were chosen, and compared with those from the standard one. Also, in order to evaluate the performance of discharged foam agents used to protect structures from heat and fire damages, the thermal characteristics of fire-protection foams were experimentally investigated. A simple repeatable test for fire-protection foams subjected to fire radiation was developed. This test involves foam generation equipment, a fire source for heat generation, and data acquisition techniques. Results show that the bubble size of foam is increased by large inside diameter of orifice or closed air hole, but phenomenon of discharge angle and expansion ratio is opposite. For the case of the open air hole, liquid film of a circular cone discharges with formation, growth, split and fine grain. In case of the closed air hole, a pillar of foam solution discharges with that. Though the temperature gradient in the foam increases with increased foam expansion ratio. it is not change with increased intensity of heat flux.