• Journal of the Society of Naval Architects of Korea
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• v.44 no.2 s.152
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• pp.83-92
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• 2007

To improve the fire safety of ships, it is required to prepare the systematic design guideline for fire protection and the way of assessing fire characteristics quantitatively. The introduction of simulation technique based on fire engineering is useful to assess fire safety performance quantitatively. Fire simulation tools are currently developing with U.S.A., Europe and Japan as a leader. Most of current fire simulation tools were developed for building or inland structure. Therefore it is required validation process and development of data base to apply maritime environments. In this paper, I/O parameters of simulation tools such as CFAST and BRI2002 of zone model and FDS and KFX of field model analysed, and designed data base considering maritime environment. The fire simulation for the pool fire model of engine room and its adjacent compartments is performed and evaluated the results.

• Journal of the Korean Society of Safety
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• v.19 no.1
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• pp.44-48
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• 2004

The smoke and toxic gases generated from the building fires are proved to cause human death. Therefore, the necessity and significance of smoke control have been emphasized, and lots of studies for developing improved smoke management system have been carried out. In this study, the experiments were conducted to evaluated a function and performance in newly developed smoke management system using mechanical pressurization. As a result of this experiment, the differential pressure was 40Pa${\sim}$60Pa and the air velocity through the door was 0.7m/s between safety zone and fire zone. The functional pressure control equipment which could make proper pressure and maintain differential pressure between safety zone and fire zone was developed. And it will give a lot of helps to evacuation activity for peoples in building and fire fighting.

• International Journal of Air-Conditioning and Refrigeration
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• v.10 no.3
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• pp.117-128
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• 2002

This paper describes the smoke filling process of a fire field model based on a self-deve-loped SMEP (Smoke Movement Estimating Program) code to the simulation of fire induced flows in the two types of atrium space containing a ceiling heat flux. The SMEP using PISO algorithm solves conservation equations for mass, momentum, energy and species, together with those for the modified k-$\varepsilon$ turbulence model with buoyancy production term. Also it solves the radiation equation using the discrete ordinates method. Compressibility is assumed and the perfect gas law is used. Comparison of the calculated upper-layer average tempera-ture and smoke layer clear height with the zone models has shown reasonable agreement. The zone models used are the CFAST and the NBTC one-room. For atrium fires with ceiling glass the ceiling heat flux by solar heat causes a high smoke temperature near the ceiling. However, it has no effect on the smoke movement such as the smoke layer clear heights that are important in fire safety. In conclusion, the smoke layer clear heights that are important in evacuation activity except the early of a fire were not as sensitive as the smoke layer tem-perature to the nature of ceiling heat flux condition. Thus, a fire sensor in atrium with ceiling glass has to consider these phenomena.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.2533-2538
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• 2014

In this study, 2-zone model CFAST software was used to predict the fire hazard of karaoke. Model is a three-dimensional unsteady state. Accuracy of CFAST is verified by comparing result of CFAST analysis with result of real fire experiment. For analysis results, the oxygen concentration were reduced to 10% within 5 minutes in room 5, the carbon dioxide concentration were increased to 5%. Therefore, at the enclosed space like karaoke, we can predict that dangerous situation would occur and people be suffocated because of toxic gas.

• Fire Science and Engineering
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• v.20 no.4 s.64
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• pp.13-18
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• 2006

The fire protection regulation for the nuclear power plants is based on the qualitative fire hazard assessment and the quantitative fire risk analysis, and the fire risk is managed by the fire protection plan with the appropriate balance among the fire prevention, fire suppression and the minimization of the fire effect. In these days, the zone model or the field model is generally used for the detail evaluation for the fire risk. At this paper, with consideration of the present trend, we evaluate whether the quantitative fire risk analysis and the assessment of fire result for fire areas at nuclear power plants can be possible by use of Fire Dynamics Simulator (FDS) that is the state-of-the-art fire modeling tool. Consequently, it is expected that the quantitative fire risk evaluation propelled by the fire modeling can be available as an applicable tool to improve the core damage frequency as well as the quantitative fire risk analysis.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.163-166
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• 2011

본 연구는 Zone Model을 활용하여 장대도로터널의 화재성상 예측방법의 고찰을 목적으로 1/5 Scale 모형실험 및 MLZSUZUKI 결과 분석과 CFD와 MLZ의 비교 분석을 실시하였다. Modeling한 모형터널의 해석시간이 MLZ 1분, FDS 약 6시간으로 CFD에 비하여 360배의 시간 감소와 다층으로 구분하여 구간의 온도변화 및 환기풍에 의한 열기류의 움직임 등의 상황이 해석됨으로 향후 MLZ을 활용하여 터널화재의 위험성 예측에 용이할 것으로 판단된다.

• Magazine of the Korea Concrete Institute
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• v.7 no.2
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• pp.117-125
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• 1995

In this study, the damage to a concrete br~dge pier due to flre caused by the fall of an oil truck were investigated by the use of FEM and by tensile tests for reinfortements. And thtse results were analyzed and compared with the measured values. In the FEM calculations, the selected variable was the fire temperature $T_a=500-800^{\circ}C$. The fixed values were the heat transition coefficient ${\alpha}=2000W/m^2{\cdot}K$. the initial temperature of concrete $T_0=5{\circ}C$ and the fire duration t=30 minutes. As the results obtained from numerical calculations, the property darrlage zone ap,)eared to be 1.5-4.1cm and the structure damage zone appeared to be 8.7- 10.1cm from the concrete surface. And this results give values very similar to those measured, nanlelv 2-4cm and 8~10cm respectively. The results frorn tensile tests give no serious loss of the tensile strength.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1384-1388
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• 2003

In structural fires, flashover is characterized by the rapid transition in fire behavior from localized burning of fuel to the involvement of all combustibles in the enclosure. An investigation of parameter effects on the time to reach flashover conditions in a typical single room fire is undertaken using a zone method (FAST) and Thomas method. Major parameters affecting the time to reach flashover are found to be fire growth rate, ventilation opening area and internal room surface. The results of the FAST and the Thomas Method give very similar results of the time to reach flashover..

• The Journal of the Convergence on Culture Technology
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• v.10 no.2
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• pp.419-427
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• 2024

This study assessed the potential impact of gas leakage resulting from accidental damage to buried urban gas pipelines during perforating operation near subway construction sites. The risk of explosions due to ignition sources such as static electricity, arising from gas infiltrating the subway construction site through storm sewers and sewage pipes, was evaluated using the ALOHA program. The results of the threat zone calculation, which input various parameters of urban gas pipelines such as length, diameter, and pressure, indicated that the flammable area within the vapor cloud extended from 1.2 to 1.4 km (red zone), the blast area ranged from 0.8 to 1.0 km (yellow zone), and the jet fire extended from 45 to 61 m (red zone). This study demonstrates that within the flammable area of the vapor cloud, a specific combination of concentration and conditions can increase flammability. The blast area may experience explosions with a pressure of 1.0 psi, sufficient to break glass windows. In the event of a jet fire, high temperatures and intense radiant heat exposure lead to rapid fire propagation in densely populated areas, posing a high risk of casualties. The findings are presented in terms of the sphere of influence and threat zone ranges.

• Fire Science and Engineering
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• v.12 no.2
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• pp.29-42
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• 1998

The use of computer supported fire safety engineering calculations has grown significantly in recent years and will be increased rapidly. In this study, in order to examine for fire dynamics of the enclosed compartment with window glass(3mm, 4mm thickness) when the window glass breaks, we conducted numerical computer simulations about foam sofa fire with the zone type computer mode, FASTLite package(version 1.1.2) and the Berkeley algorithm for breaking window glass in a compartment fire, BREAK1 program (version 1.0). The analysis of the results in this paper shows that there are differences of fire dynamics between open-or enclosed-state compartment fire and the enclosed compartment fire with window glass breaking. It is also shown in this study that backdraft phenomenum occurs due to accumulated unburned combustible fuel when the glass of 4mm thickness breaks, and that temperature differences between the inner-and outer-surfaces of 3mm and 4mm thick glasses are appreciable. This study will help fire fighter to establish fire suppression or occupant's refuge strategies and fire safety engineer to enhance simulation techniques about the five dynamics of compartment fire.