• 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 the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.136-143
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• 2006

This study was conducted to determine the amount of unprotonated nicotine in cigarette mainstream smoke and to investigate its relationship to level of filter ventilation and machine smoking conditions. Unprotonated nicotine from TPM trapped on a Cambridge filter pad(CFP) was adsorbed by Carboxen/PDMS SPME fiber, thermally desorbed and determined by GC/MS. 2R4F reference cigarette, twelve commercial brands from the Korean market and five test cigarette samples, which had the same tobacco blend with different levels of filter ventilation, were analyzed for unprotonated nicotine. In commercial brands, the amount of unprotonated nicotine changed slightly depending on the pH values of smoke, and decreased as the tar level increased. filter ventilation in these commercial cigarettes was $28{\sim}80%$ and the higher filter ventilation increased relative unprotonated nicotine levels, but not significantly. However, in five test cigarettes with different filter ventilation$(0{\sim}70%)$, unprotonated nicotine levels increased almost linearly with the level of filter ventilation. Concentrations of unprotonated nicotine in mainstream smoke generally increased in order $HC\;<\;ISO\;{\leq}\;MDPH$ machine smoking conditions. The ratio of unprotonated nicotine to total nicotine among $cigarettes({\alpha}_{fb})$ increased in order RC < MDPB < ISO conditions. Concentrations of unprotonated nicotine varied with three machine smoking conditions.

• Fire Science and Engineering
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• v.17 no.2
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• pp.56-61
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• 2003

The smoke removal rate from a room with an opening was investigated for different smoke control systems by using the large eddy simulation turbulence model of the Fire Dynamics Simulator. The decreasing rate of the particles randomly distributed in the 2m X 2m X 2.4m room was com-pared for the ventilation system, pressurization system and extraction system, and for the air flowrate of the ventilation system. Difference in the smoke removal rate among the three smoke control systems was small when the opening was closed. The pressurization system showed less smoke removal rate than the other two systems when the opening existed, and hence is not recommended for subway stations with large openings. It was also shown that a less flowrate in the ventilation system leads to a much longer smoke removal time.

• Journal of the Korean Society of Safety
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• v.18 no.3
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• pp.34-38
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• 2003

The large eddy simulation based Fire Dynamics Simulator was utilized to investigate the effects of the size of an opening on smoke removal performance for the three smoke control systems-ventilation purge, and extraction. Three different opening sizes, $r_A$=1, 2, and 3 were investigated while the flow rate remained 0.75 $m^3/s$ at the inlet or outlet depending on the systems. Increase of the opening size did not give a significant difference in the smoke removal rate for the three smoke control systems, though the increasing opening size slightly improved smoke removal. The extraction system was shown the best smoke control system, and the purge system yielded low performance compared to the other two systems for all the different opening sizes.

• Fire Science and Engineering
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• v.22 no.2
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• pp.38-43
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• 2008

Recently, the application of transverse ventilation system in accordance with oversized exhaust ports has been increased in bidirectional road tunnel in order to improving smoke exhaust ability. In this study, numerical simulations were carried out by using FDS (ver. 4.0) which includes variations of exhaust flow rates and heat release rate of fire to obtain the optimal smoke exhaust rate in case of fire in the transversely ventilation system. As a result, smoke exhaust amount tends to increase when the inner velocity is existing in the tunnel. In case of internal longitudinal air velocity 2.5m/s face to the fire, smoke moving distance should be restricted within 250m when the smoke exhaust rate which exceeds $244.8m^3/s$.

• Fire Science and Engineering
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• v.22 no.2
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• pp.49-56
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• 2008

Smoke propagation for the Daegu Metro fire is reproduced by a reduced-scale model experiment. The three-story station building was modeled with 1/20-scale, and the tunnel connected to the platform was not completely modeled because of its length. To include the flow resistance the tunnel provides the mesh screens were used in the model. The fire scenario was selected based on the fire growth rate of the metro car seat where the fire initiated. The time when smoke arrived at each compartment in the station building was measured by thermocouples and visualization. Regarding fire ventilation, the air supply that has been accepted as conventional design in a subway metro building intensifies smoke spread. The results show that the whole building was filled with smoke in about 10 minutes in case of no ventilation.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1996.11a
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• pp.30-33
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• 1996

This paper presents the technical basis for hot smoke test intended to investigate the effectiveness of smoke ventilation system in both high-rise building and those containing atria and/or galleria. Smoke is particularly serious hazard in these building in which considerable time is required for complete evacuation. It is widely recognised that the effectiveness of large smoke ventilation system can be difficult to confirm by a critical analysis of the system design calculation. Thus a hot smoke test is recently introduced through the experiences of many attempts. Diffusion flames used for hot smoke test have a higher flame length, so that those can not be applied to small compartment. Therefore the objective of this paper is introducing the method of flame control which can be applied to any size of compartment

• Journal of computational fluids engineering
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• v.11 no.4 s.35
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• pp.20-25
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• 2006

In the present study, flow characteristics inside a road tunnel are simulated for the ventilation flows due to jet fan system and flows induces by the traffic. Traffic ventilation is numerically simulated by multiple reference frame. From the results of steady state simulation of tunnel ventilation, it is found that the proper ventilation is achieved by the designed jet fan system along with ventilating flow induced by the traffic. A transient simulation is also performed for the case of vehicle fire in the tunnel reversing the direction of rotation of some fans. The results suggest that the heat and smoke can be controlled by the proper changing of fan operation mode. The present results can be used to design proper ventilation system and effective smoke control system as well.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.468-473
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• 2008

Currently, most of the buildings have been the high-rise buildings and not only the damage for people but also loose of property have been increased significantly. Furthermore, the damage for residents in indoor is increased significantly, the law related to fire protection is not established yet. We discussed safety of evacuation according to unitary system in standard apartment. At a result, when installing the smoke ventilation system, the RSET has been achieved and delay effect for reaching time of CO and smoke area has been obtained.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.9
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• pp.721-736
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• 2019

In this paper, the behavior of the fire smoke due to the operation of the ventilation systems when the fire occurred in the underground station (6 basement floors) and the tunnel at the great depth was measured. Fire smoke was generated by using a smoke generator which realized heat buoyancy effect by using hot air blower. The two locations of the fire were selected on the platform and on the platform of the tunnel located outside the screen door. A ventilation mode is generally used in which smoke is exhausted through a vent hole provided in a platform when a platform fire occurs. The tests were performed by operating the exhaust through the ventilation holes of the tunnel part located at both ends of the platform. The smoke density and the wind speed/velocity were measured at various positions, and the videos were taken to analyze the movement and smoke of the smoke. In both cases for fire inside the platform and in the railway tunnel, due to the ventilation mode operation of the fan for the platform and the exhaust of the fans in the tunnel smoke were well exhausted and the smoke propagation to the area near the smoke zone was suppressed. The smoke-control mode, which is applied to both fans for the platform and fans for in the tunnel at both ends of the platform, can provide a safer evacuation environment to the passengers from the fire smoke when the platform fire or fire train stops.