• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.04a
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• pp.239-244
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• 2011

This study is aimed to develop fundamental technology on the smoke control method by simulation model and scale model simulation technique in pressure differential systems. Thereby, this research aimed to establish design elements and technologies required for smoke control system that is suitable to pressure differential systems of the high-rise buildings in order to minimize the loss of lives and property damage in case of fire.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.2
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• pp.81-86
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• 2008

In this study, numerical simulations were carried out to analyze the effect of the smoke extraction system and fire shutters in subway station fires using FDS 4.0. Subway station used in the experiment was 205 m long. Simulation results are validated by comparing with experimental results. Simulation results showed good agreement with experimental results within $20\;^{\circ}C$. 20 MW polystyrene was used as a fuel in the numerical prediction. Numerical predictions were performed in the side-platform type subway station in case of a train fire. Temperature and CO concentration were lowered by the operation of smoke extraction system.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.107-110
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• 2008

This study is aimed to develop fundamental technology on the smoke control method by simulation model and scale model simulation technique in underground space. Thereby, this research aimed to establish design elements and technologies required for smoke control system that is suitable to underground spaces of the high-rise residential-commercial and office buildings in order to minimize the loss of lives and property damage in case of fire.

• Journal of the Korean Society for Railway
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• v.10 no.3 s.40
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• pp.313-318
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• 2007

In this study, numerical simulations were carried out to analyze the effect of the smoke extraction system and fire shutters in subway station fires using FDS 4.0. Subway station used in the experiment was 145 m long. Simulation results are validated by comparing with experimental results. Simulation results showed good agreement with experimental results within $10^{\circ}C$. 10 MW polystyrene was used as a fuel in the numerical prediction. Numerical predictions were performed in the center-platform type subway station in case of a kiosk fire. Temperature and CO concentration were lowered by the operation of smoke extraction system. But, the operation of fire shutters had little effect on temperature and CO concentration in the platform level.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2885-2890
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• 2011

Simulation study were performed for fire location effect on the smoke spread in the deeply-underground subway station(DUSS). In this research, Shingumho station (The line # 5, Depth: 46m) has been selected as case-study for the analysis of smoke-spread effect with the different fire location. Field test data measured for actual fan in DUSS was applied as a condition of a simulation. The whole station was covered in this analysis and 4 million grids were generated for this simulation. The fire driven flow was analyzed case by case to compare the smoke-spread effect according to the fire location. In order to enhance the efficiency of calculation, parallel processing by MPI was employed and LES(large eddy simulation) method in FDS code was adopted.

• Fire Science and Engineering
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• v.17 no.3
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• pp.7-12
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• 2003

A 50 kW polyurethane fire in a compartment of 4 m ${\times}$ 1 m ${\times}$ 1.5m with large openings similar to a subway station was simulated by a large eddy simulation to investigate the fire and smoke control. The NIST FDS, which employed a mixture fraction combustion model and a finite volume method for radiation, was utilized. Distribution of temperature and smoke particles was compared with in the lower and upper corridors for three different smoke control systems, ventilation, purge, and extraction, starting in 5 sec from the ignition of the fire. For the given geometries, the ventilation system showed the best smoke removal rate and lowest temperature distribution in the both corridors. It was confirmed that the purge system is not recommended for a subway station since the smoke removal rate of the purge system was worse than that without a smoke control system.

• Fire Science and Engineering
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• v.32 no.6
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• pp.15-21
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• 2018

This study examined the flow characteristics of fire smoke under pressurized air ventilation conditions by carrying out fire simulations on multi-compartment enclosure, including room, ancillary room and stair case. Fire simulations were conducted for the air-leakage test facility, which was constructed to measure the effective leakage area and aimed to improve the understandings of fire and smoke movement by analyzing the overall behaviors of fire smoke flow and pressure distributions of each compartment. The simulation results showed that the heat release rate of the fires was controlled sensitively by the amount of air supplied by the ventilation system. An analysis of the velocity distributions between the room and ancillary room showed that fire smoke could be leaked to the ancillary room through the upper layer of the door, even under pressurized air supply conditions. From these results, it was confirmed that the fire size and spatial characteristics should be considered for the design and application of a smoke control system by a pressurized air supply.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.5
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• pp.1-7
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• 2010

Since subway fire disaster at Daegu, Korea smoke control system and passengers evacuation distance has been focused to reform. Existing smoke control facilities need to expand volume of ventilation capacity however, the complicate subway station structure can hardly react dispersion of smokes from massive subway cabin fire. Smoke flow at platform level move upward thought vertical stairway and passengers evacuation goes with same direction. The victims of evacuees from subway station fire mainly due to exposure of heat radiation and smoke. The study demonstration the effect of downward evacuates stairway system by separating evacuation route to smoke movement pass way including saving times of evacuation.

• 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.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.9
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• pp.3712-3729
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• 2020

Smoke detection is helpful for early fire detection. With its large coverage area and low cost, vision-based smoke detection technology is the main research direction of outdoor smoke detection. We propose a two-stage smoke detection method combined with block Deep Normalization and Convolutional Neural Network (DNCNN) and visual change image. In the first stage, each suspected smoke region is detected from each frame of the images by using block DNCNN. According to the physical characteristics of smoke diffusion, a concept of visual change image is put forward in this paper, which is constructed by the video motion change state of the suspected smoke regions, and can describe the physical diffusion characteristics of smoke in the time and space domains. In the second stage, the Support Vector Machine (SVM) classifier is used to classify the Histogram of Oriented Gradients (HOG) features of visual change images of the suspected smoke regions, in this way to reduce the false alarm caused by the smoke-like objects such as cloud and fog. Simulation experiments are carried out on two public datasets of smoke. Results show that the accuracy and recall rate of smoke detection are high, and the false alarm rate is much lower than that of other comparison methods.