• 한국안전학회지
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• 제21권6호
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• pp.46-54
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• 2006

Fire extinguishing experiment was conducted with water mist nozzle in case of the pool fire, cascade fire and spray fire on flammable liquid of class B whether water mist system can be effective system for power transformer fire scenario. In the event of a pool fire, flow rate and time to extinguish was inclined to be increased according to the obstruction rate of ignition space. Furthermore, the performance of fire extinguishing depended upon the spraying angle of the nozzles. In case of cascade fire, the effect of extinguishment was began to show from a combustion pan filled with fuel and fuel flowing plate later on.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.609-613
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• 2008

The fire whirl occurring by the instability of atmosphere is a rare phenomenon, but highly destructive because it has high inhalation and lift force, caused by the rotating velocity. And it is difficult to extinguish the fire, because of increment of the spread rate with the flame height. In this study, for investigation of the flow characteristic of fire whirl for various heat release rate, numerical analysis is performed in same conditions with experiments, using the FDS which is developed at NIST. For validating of the numerical study, the results are compared with the experiment. The result shows that the relation between the characteristic length and the ratio of circulation versus the buoyancy force is $z_f$/D$^{\ast}$ = 0.304(${\Omega}/{\alpha}$)^2 - 1.334${\Omega}/{\alpha}$ + 5.516.

• 디지털산업정보학회논문지
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• 제8권4호
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• pp.63-71
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• 2012

Recently, because most of buildings in the city become bigger and higher, so various convenient facilities and high-tech management skills are required to prevent potential disasters. Especially, because fires in huge buildings can cause serious damage, technologies and methods that help people quickly and safely to escape from the building is very important to extinguish the fire in initial state and to minimize the damage. This paper suggests a context-aware service system that can provide optimal escape routes to tenants with their smart-phones. The proposed system collects contexts with real time through USN(Ubiquitous Sensor Network) and provides an optimum escape route based on the collected contexts through service users' smart phones. In addition, The system provides not only safe routes from the fire but also valuable information for rescue operations with real time.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제25회 KOSCI SYMPOSIUM 논문집
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• pp.33-39
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• 2002

Unsteady behaviors of counterflow flame were studied experimentally in opposing jet counterflow burner using diluted methane. To generate the unsteadiness on the flame, the counterflow diffusion flame was perturbed by velocity changes made by the pistons installed on both sides of the air and fuel stream. The velocity changes were measured by Hot wire and Laser Doppler Velocimetry, and the flame behaviors were observed by High speed ICCD and ICCD. In this investigation, the spatial irregularity of the strain rate caused the flame to extinguish from the outside to the axis during the extinction, and we found the following unsteady phenomena. First, the extinction strain rates of unsteady cases are much larger than those of the steady ones. Second, the extinction strain rates become larger as the slope of the change of the strain rate increases. Third, the unsteady extinction strain rates become smaller with the increase of the initial strain rate.

• 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.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2221-2223
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• 1999

Axial magnetic field($B_z$) generated by special electrode construction in vacuum interrupters(Vl) is used to extinguish electric plasma arcs because that restrains this form expending. So VI applied axial magnetic field has more interruption capacity as compared with other VI. Also, the profile of toroidal field($B_{\theta}$) generated by $B_z$, is important to VI design. In this study, it was represented that the behavior of vacuum arc. In addition, The relationship between $B_z$ and $B_{\theta}$ was represented by using Dynamo theory. I hope that this study will be a good data in design of vacuum interrupters.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1809-1811
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• 1998

Axial magnetic field restrains arc diffusion that appear at cutting off fault current in vacuum interrupter(VI). In this study, spatial and temporal behavior simulation of arc is carried out for various axial magnetic field. Also the results of this simulation show that axial magnetic field controls and helps to extinguish arcs. This study can be applied to design and analysis of VI. Dymo theory that is not considered in this study will be considered latter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1752-1754
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• 1998

Recently the research about electron transport characteristic and energy distribute function in mixture gases within Helium, has been used and developed widely as industrial quality improvement of extinguish characteristic, electrical dielectric strength ability of application of each species high voltage apparatus, gas plasma etching progress of work to use manufacture of semiconductor, thin film molding by CVD, insulation film to use ultra LSI, etc. This paper analyze electron transport characteristic in the range E/N $1{\sim}60$[Td], pressure $0.1{\sim}6.0$[Torr] by MCS. It is necessary to seek electron drift velocity, diffusion coefficient, lonization coefficients, characteristic energy, mean energy and electron energy distribution function as electron transport characteristic.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.168-173
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• 2004

This research shows the method about the auto extinguishing system construction for the subway train's safety operation. The safety system is the total auto extinguishing system which it is able to overcome the emergency situation, to see fast using the sensing system, to interface using the communication system, finally to extinguish the large-scale fire happened. The system model is the total disaster mitigation system model preventing the arson or terror. and to apply a method of the fire extinguishing system using reinforced fire extinguishing agency in the world first. It is to use the subway train and the railroad train which is prevented and mitigated the large-scale demage the same as the arson and the terror.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권3호
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• pp.146-154
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• 2006

We derived a theory of increasing electromagnetic force which acts on arc column for reducing arcing time between electric contacts. A simulation method of arc velocity is presented by calculating blowout force using 3D FEM and drag force acting on arc column. This paper proposes 3 types arc extinguish chamber of different flux path and presents the specific electromagnetic force and arc velocity of each model by the analysis. The result of analysis and experimental proposes the prediction method of arc time when all conditions are same except external magnetic field.