• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.4
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• pp.389-400
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• 2003

In order to recommend the mechanical smoke exhaust operation mode, Subway Environmental Simulation (SES) is used to predict the airflow of the inlet and outlet tunnel for the subway station. Fire Dynamic Simulation (FDS) is used the SES's velocity boundary conditions to clarity the smoke exhaust effectiveness by the variations with mechnical ventilation system. We compared each 6 types of smoke exhaust systems for the result of smoke density and temperature distributions for 1.5m height from the subway station base in order to clarify the safety evaluation for the heat and smoke exhaust on subway fire.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2012.04a
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• pp.58-61
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• 2012

엔진나셀 화재를 둔각물체에서 분사된 연료제트 화염으로 모사하여 화염안정화 및 소화특성을 조사하기 위해 실험과 수치해석을 수행하였다. 연료제트는 공기유동에 동측류인 경우와 대향류인 경우에 사각의 둔각물체에서 분사하였고, 소화약제는 이산화탄소와 질소를 사용하여 공기유동에 희석시켜주었으며 연료로는 메탄을 사용하였다. 본 실험의 결과를 해석하고 보충하기 위하여 LES(Large Eddy Simulation)을 기반으로 하는 FDS(Fire Dynamics Simulator)를 이용하여 비반응 유동장에서의 혼합특성과 둔각물체 후류의 유동특성을 살펴보았다.

• Journal of the Society of Naval Architects of Korea
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• v.41 no.5
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• pp.48-54
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• 2004

The present study investigates the fire development characteristics on a Ro-Ro ferry vehicle using the modified FDS code considering droplet break-up. Numerical simulations are compared with model-scale tests for validation of field model. The predicted results such as smoke layer temperature and oxygen concentration are in good agreement with model-scale tests. Also, it is shown that water spray systems are very effective to control the fire development on a vehicle deck. These numerical simulations using a field model may be helpful in accomplishing the fire safety for marine vehicle.

• Journal of the Korean Institute of Gas
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• v.25 no.6
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• pp.7-13
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• 2021

Various research has been done on fires and explosions at gas stations at home and abroad. However, only studies of off-site damage in the event of fire at the gas station were conducted, and research on fire at the auxiliary facilities in the gas station was insufficient. The gas station is a place where anyone can easily access dangerous goods. As the risk of fire increases due to the recent increase of auxiliary facilities such as convenience stores and car repair shops in gas stations, it is important to detect the effects of fire on the main oil refinery in case of fire and to verify the validity of existing regulations. In this thesis, we conducted a study to find out the effect of radiation heat on the separation between fixed and fixed oil reactors in the event of fire at an auxiliary facility. Simulation was modelled using FDS 5.5.3 Version, and the size of the fire source was configured with 13 fire assessment devices and the heat emission rate per unit area was entered. Simulation shows that the separation distance of 2 m does not secure the safety of the gas pump in the event of fire at the auxiliary facilities, and radiation heat does not damage at the separation distance of at least 4 m. Accordingly, facilities that can block radiant heat in the event of fire at auxiliary facilities, and measures to limit the use of auxiliary facilities or to re-impose the separation between buildings and fixtures will be needed.

• Journal of Navigation and Port Research
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• v.40 no.4
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• pp.189-196
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• 2016

We propose a virtual sailor training platform which supports emergency drills for ship's fire in virtual environment. Proposed platform not only enhances training efficiency by providing immersiveness, but also enables a consolidated virtual training due to the network-based multiplayer capabilities. Based on the offline fire simulation results using FDS and CFAST the platform visualizes a realistic fire spread in real-time. The training platform on the basis of the fire training material of the maritime safety education institute induces equipment proficiency and environment adaptation throughout immersive virtual environment in addition to procedure proficiency as well. In the implementation we showed that the equipment and environment controls and telepresence improve the training proficiency and enable collaborative virtual training that participates multiple trainees and induces cooperation for a common goal. Implementation of the platform demonstrated the skill mastery capability of the drill such as efficient fire apparatus controls and passenger controls.

• Journal of the Korea Safety Management & Science
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• v.17 no.2
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• pp.117-127
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• 2015

This study investigated the smoke blocking and control systems for the safety of residents evacuation and for the prevention of smoke spread through the central corridor in the event of central corridor type of intelligent building fire. We offered additional ways of utilizing smoke ventilators and intake ventilation equipment and utilized CFD-based fire simulation program(FDS Ver.5.5.3) in order to analyze the effect. As a result, many differences in the smoke block effect, depending on the application of smoke ventilator and location of installation, was found. In addition, the result was found that larger effect was showed not in the case of application of smoke ventilator in central corridor only but application in fire room. The reason is that the smoke leakage is blocked primarily as air is flowed in the fire room through open door by operation of intake smoke ventilator in the public corridor and secondarily, the smoke leakage to the public corridor could be blocked as fire and smoke were released to the opened smoke ventilator continuously. Especially, the effect was maximized through complex interactions by applying smoke ventilator and intake ventilation equipment in corridor together rather than applying smoke ventilator and intake ventilation equipment independently. The proposed measure through this study shall be considered from architectural plan as one of ways for blocking from smoke spread to the central corridor in the central corridor type of intelligent building. In addition, flaws on regulation shall be established and supplemented.

• Journal of computational fluids engineering
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• v.21 no.4
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• pp.40-45
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• 2016

The numerical simulation has been performed to predict the performance of the fire suppression system for cabin of shipboard enclosure. The present study aims ultimately at finding the optimal parametric conditions of the mist-injecting nozzles using the CFD methods. The open numerical code was used for the present simulation named as FDS (Fire Dynamics Simulator). Application has been done to predict the interaction between water mist and fire plume. In this study, the passenger cabin was chosen as simulation space. The computational domains for simulation in the passenger cabin were determined following the fire scenario of IMO rules. The full scale of the flow field is $W{\times}L{\times}H=4{\times}3{\times}2.4m^3$ with a dead zone of $W{\times}L{\times}H=1.22{\times}1.1{\times}2.4m^3$. The water mist nozzle is installed in ceiling center of 2.3 m height from the floor, and there are six mattresses and four cushions in the simulation space. The combination patterns of orifices to the main nozzle and the position to install nozzles were chosen as the simulation parameters for design applications. From the present numerical results, the centered-located nozzles having evenly combined orifices were shown as the best performance of fire suppression.

• Fire Science and Engineering
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• v.33 no.3
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• pp.112-120
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• 2019

To improve the reliability of a safety assessment using a fire simulation in domestic PBD, the evaluation method of ASET considering the uncertainties of the input parameters and numerical model of fire simulation was carried out. To this end, a cinema and officetel were selected as the representative fire spaces. The main results were as follows. Considering the uncertainty of the heat release rate, which has the greatest effect on the major physical quantities presented in the life safety standard, significant changes in temperature, CO, and visibility occurred. In addition, when the bias factors reflecting the uncertainty of the numerical model were applied, there were no significant changes in temperature and CO concentration. On the other hand, the visibility was increased considerably due to the low prediction performance of smoke concentration in FDS. Finally, the reason why the physical quantity determining the ASET in domestic PBD is mainly visibility was discussed, and the application of uncertainty of the input parameters and numerical model in a fire simulation was suggested for an accurate ASET evaluation.

• Journal of the Korean Society of Safety
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• v.30 no.1
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• pp.14-20
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• 2015

A Large Eddy Simulation(LES) was performed for the prediction of unsteady dispersion behavior of hydrogen fluoride (HF). The HF leakage accident occurred at the Gumi fourth industrial complex was numerically investigated using the Fire Dynamics Simulator (FDS) based on the LES. The accident area was modeled three-dimensionally and time-varying boundary conditions for wind were adopted in the simulation for considering the realistic accident conditions. The Message Passing Interface (MPI) parallel computation technique was used to reduce the computational time. As a result, it was found that the present LES simulation could predict the unsteady dispersion features of HF near the accident area effectively. The dispersion behaviors of the leaked HF was much affected by the unsteady wind direction. The LES could predict the time variation of the HF concentration reasonably and give an useful information for the risk analysis while the prediction with the time-averaging concept of HF concentration had a limitation for the amount of HF concentration at specific location point. It was identified that the LES is very useful to predict the dispersion characteristics of hazardous chemicals.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1794-1801
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• 2008

Fire-driven flow and temperature distribution in a ventilated tunnel was analyzed by Large Eddy Simulation using FDS code. The simulated tunnel is 182m length, 5.4m wide and 2.4m height. A pool fire was located 112m from tunnel entrance and was taken as a heat source of $0.89m^2$. The heat is assumed to be released uniformly throughout the whole simulated time. The fire strength was 2.76MW and the fuel burnt was octane. The parallel computational method was employed to accelerate the computing time and manage the large grid points which is not possible to handle in the one CPU. The total grid points used were $2.4{\times}10^6$ and 7 CPUs were used to calculate the momentum and energy equations. The simulated results were well compared with the experiments.