• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.05a
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• pp.227-230
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• 2002

환경문제를 야기하는 할론 소화설비의 사용이 금지되면서 대체소화설비로 관심을 끌며 연구되기 시작한 미세물분무 소화설비이다. 미세물분무는 고압에서 물을 방사하여 $Dv_{0.99}$가 1,000$\mu$m 미만의 물입자를 만들며 작은 물입자로 인해 표면적의 증가와 증발특성이 우수하고, 산소농도를 감소시키는 질식작용과 화염의 냉각작용에 의해 소화작용을 상승시킨다. 이러한 미세물분무의 소화작용에 대한 소규모 화재실험을 기반으로 유류화재의 진압$\cdot$소화특성에 대한 실용화를 위해 실제크기 화재실험을 하였다.(중략)

• Fire Science and Engineering
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• v.30 no.4
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• pp.14-19
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• 2016

When an interior fire occurs in an apartment building, pollution of the entrance area by fire smoke before an air fan operates makes the evacuation of people very difficult aswhen the fire doors are opened. Numerical simulations using Fire Dynamics Simulator were conducted to determine the impact of a sprinkler on the fire flow velocity. The fire flow velocity was compared depending on the presence of sprinklers and the sprayed droplet size. The configuration and actual dimensions of an apartment building were used in the numerical simulations. The simulation results showed that fire flow velocity becomes smaller when a sprinkler is installed. In addition, the smaller droplet size results in a smaller fire flow velocity because smaller droplets can be evaporated more easily.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7964-7970
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• 2015

In enclosed areas such as railway tunnels, the heat and smoke generated by a fire can pose a tremendous risk to the life of passengers. To prevent or mitigate such scenarios, fire detectors are installed for early fire detection. This numerical study is preformed for establishing the method of detecting performance of fire detectors installed on railway tunnels. Numerical analysis are conducted using the fire dynamics simulator, developed by the NIST. The temperature of the tunnel walls is determined using the assumed exterior structure of the tunnel. In addition, the detection times of detectors installed at different locations in the tunnel are obtained for different sizes of the fire source, and the results are compared and analyzed.

• Fire Science and Engineering
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• v.17 no.4
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• pp.105-110
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• 2003

In Part II, the temperature and smoke particle distributions of the extraction system, which yielded the best smoke removal performance among the three smoke control systems in Part I, for extraction flowrates of 0.6∼2.4 ㎥/s and two fire sizes of 200 ㎾ and 2 ㎿ were presented. The same numerical method was utilized to the same computational domain and configurations as Part I. It was shown that the extraction flowrate affects the smoke control performance significantly, and that a similar trend in improving the smoke removal performance with the increasing extraction flowrate between the two fire sizes. An extraction flowrate of 2.4 ㎥/s or higher was required for the temperature in the escape route less than $^{\circ}C$ for the given situations.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.10a
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• pp.297-301
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• 2010

일반콘크리트 기둥을 대상으로 콘크리트 피복두께와 단면크기를 변수로 하여 내화성능을 평가하였다. 피복두께가 늘어남에 따라 내화성능시간도 다소 늘어 피복두께와 내화성능은 비례적 관계에 있는 것으로 나타났다. 단면크기가 커짐에 따라 실험체의 열용량이 증가하여 내화성능이 좋아질 것으로 예상하였으나 폭렬의 영향으로 인하여 단면크기에 따른 내화성능의 변화는 큰 의미가 없는 것으로 나타났다. 따라서 콘크리트 기둥의 내화성능은 폭렬 여부에 의해 크게 지배되는 것으로 판단된다.

• Fire Science and Engineering
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• v.25 no.2
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• pp.132-137
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• 2011

A relationship between resisting moment and the structure of an automatic closure device is introduced for analyzing the effect of opening and closing condition on various fire door sizes in the pressurized room for smoke control system. The larger the size of fire door is, the more force is required for reaching to opening and closing conditions and there exists the design range of fire door in the pressurized room reflecting the closing time of fire door, rotative velocity, a relation between rotative angle and force and the efficiency of the automatic closure device.

• Fire Science and Engineering
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• v.21 no.3
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• pp.61-68
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• 2007

The purpose of this study analyzes heat flows and fire behavior through a reduced-scale model experiments about change of wind velocity in underground life space. When the wind velocity is increased the temperature rise time of the fire room was risen fast. And temperature of fire room was increased. And increase of wind velocity displayed maximum temperature at an opening of the fire room. Heat flows by fire spread increase size of smoke occurrence and flame, and displayed high temperature distribution in passageway than inside of neighborhood department promoting eddy flow spread as wind velocity increases. Finally, heat flows are decided by wind and wind velocity at fire of underground life space, and Wind velocity increases, temperature increase and decrease could confirm that is gone fast.

• Fire Science and Engineering
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• v.21 no.2 s.66
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• pp.98-104
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• 2007

This study is related with the fire risk assessment for fire area at nuclear power plant by use of FDS (Fire Dynamics Simulator) that is a computational fluid dynamics (CFD) model of fire-driven fluid flow. The major purpose of this research is to analyze the sensitivity of the fire modeling when the heat release rate that is an important input variable is changed as well as when the grid size that is a critical factor of the fire model is modified. The result is presented at the conclusion with some comments for CFD model application.

• Fire Science and Engineering
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• v.29 no.5
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• pp.34-41
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• 2015

The applicability of plate thermometer (PT), which feature simple installation and low cost, was experimentally examined in steady and unsteady-state fire conditions. An infrared radiation heater and a square burner with C3H8 as fuel were used as heat sources. The relative measurement accuracy of the PT was evaluated by comparing measurements made using a Gardon-type heat flux meter. From a practical point of view and in terms of measurement accuracy, the optimal size and thickness of the PT in steady and unsteady-state fire conditions were 100 mm and 0.6 mm, respectively. These results can be explained by the conductive heat losses and thermal inertia of the PT for different sizes and thicknesses. It can be also concluded that measurements of heat flux using the PT in conditions of faster fire growth rate than slow require considerable attention.

• Tunnel and Underground Space
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• v.15 no.1 s.54
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• pp.55-60
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• 2005

In this study, the 1/20 reduced-scale experiments using Froude scaling were conducted to investigate the effect of longitudinal ventilation on the variation of burning rate in tunnel fires. The methanol square pool fires with heat release rate ranging from 3.57 kW to 10.95 kW were used. The burning rate of fuel was obtained by measured mass using load cell and temperature distribution were measured by K-type theomocouples in order to investigate smoke movement. The wind tunnel was connected with one side of the tested tunnel, and logitudinal ventilation velocity in the tested tunnel was controlled by power of the wind tunnel. In methanol fire case, the increase in ventilation velocity decreased the turning rate due to the direct cooling of fire plume. For the same dimensionless velocity(V), homing rate decreased as the size of pool fire increased.