• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.12
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• pp.1359-1365
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• 2014

In this study, 1-way fluid structure interaction analysis(FSI) for the shutter, component of side jet thruster was performed to evaluate the safety. Driving torque to open nozzle, thermal and high pressure load of hot gas was applied to shutter. Thus, the shutter must be designed to endure this load during combustion. We carried out computational fluid dynamics analysis to obtain the pressure, temperature, and heat transfer coefficient of hot gas of side jet thruster. We then used the data as the load condition for a thermal structural analysis using a mapping method. The locations with the maximum stress and temperature distributions were found. We compared the maximum stress with the tensile stress of shutter material according to temperature to evaluate the safety. We also analyzed the radial deformation of the shutter to set the proper interface gap with the side jet thruster parts.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.3
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• pp.182-192
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• 2022

This study analyzed the effects of the all-in-one automatic fire shutter (hereinafter referred to as "all-in-one shutter") installed along the fire compartment in a five-story high school building on the evacuation time by using the Pathfinder simulation program. When the all-in-one shutter was added as a new variable, the evacuation time was delayed, indicating insufficient evacuation safety. The evacuation time exceeded the appropriate standard when the evacuation exit was designated to the students in the present state of being placed on the 2nd, 3rd, and 4th floors and the all-in-one shutter was activated. When students were placed on the 1st, 2nd and 3rd floors under the same conditions, the evacuation time was also greatly exceeded. However, when the width of the entrance was set to 130cm, the evacuation time was almost the same as when the all-in-one shutter was not installed. In high-rise school buildings, the bottleneck caused by all-in-one shutters is becoming a major factor in evacuation barriers. To ensure the evacuation safety of school buildings, it has been judged that evacuation education and training to predict the evacuation time required through the all-in-one shutter entrance and induce an evacuation procedure suitable for the standard evacuation time should be carried out in parallel. The implications of this study and suggestions for effective fire compartments and follow-up studies were discussed.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.264-267
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• 2006

This paper describes the accident analysis by modeling the current transformer mounting in meaium voltage metal-clad switchgear(MCSG). In analyzing the accident the reconstruction at the current transformer mounting(VCB connecting guide) has to be taken into account. The accident was modelled as a 3-phase ground fault mounting between the end plate of a high voltage lines and the safety shutter at the current transformer mounting of the VCB inside the metal clad switchgear. Since the outside maintenance of the metal clad switchgear is restricted by the enclosed compartments, its circumference has to be kept clean. Through the reconstruction results, it was confirmed that the fault of the enclosed switchboard could be reduced when the shutter made of Fe material was changed into an insulation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.295-296
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• 2021

With the recent diversification and complication of buildings, the functions of building are also developing. As much as the development of buildings, the machine or equipment used for them is also developing. Thus, all sorts of domestic/foreign industrial facilities and fire stations in the whole nation are using the electric shutter that could meet the insulation just like the exterior wall of general buildings, for bringing-in/storage and crime prevention/fire prevention. Currently, various types of electric shutters are used. Such wrong operation and poor management are causing many panel-falling accidents. This study researched the reduction of electric shutter panel-falling risk by reviewing the domestic/foreign laws and standards, and researching the new safety equipment. First, the causes for falling and accident types were drawn by analyzing the cases of electric shutter accidents. After that, a checklist as the measures for reducing the falling of electric shutter in building was suggested by analyzing the items for the inspection of electric shutter.

• Fire Science and Engineering
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• v.32 no.2
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• pp.82-91
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• 2018

This study analyzed the working conditions and problems of screen fire shutters in the Goyang Bus Terminal fire based on the fire investigation results. At that time, screen fire shutters in the 1st basement, which was under construction, did not work because the power was shut off. Four screen fire shutters in the 1st and 3rd floor did not work despite the power not being shut off. The following problems related to a screen fire shutter were found: shutting off the power to screen fire shutters for the fire compartment on each floor, even when the fire compartments were changed in each area; installing an integral type screen fire shutter without any regulations, installing a two-stage screen fire shutter in a place not related to obstacles during evacuation; stopping the function of the screen fire shutters for a fire compartment on each floor after a combustible sandwich panel was comparted; installing a screen fire shutter over 10 meters in width, in which its performance was not verified; and no safety control standards for reinstalling or maintaining a screen fire shutter.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.55 no.2
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• pp.110-114
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• 2006

This paper describes the accident analysis by modelling the current transformer mounting in a metal-clad switchgear at 22.9kV. In analyzing the accident, the reconstruction at the current transformer mounting(VCB connecting guide) has to be taken into account. The accident was modelled as a 3-phase ground fault occurring between the end plate of 22.9kV lines and the safety shutter at the current transformer mounting of the VCB inside the metal clad switchgear. Since the outside maintenance of the metal clad switchgear is restricted by the enclosed compartments, Its circumference has to be kept clean. Through the reconstruction results, it was confirmed that the fault of the enclosed switchboard could be reduced when the shutter made of Fe material was chanted into an insulation.

• Fire Science and Engineering
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• v.30 no.5
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• pp.36-45
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• 2016

Integral fire shutters are installed indiscriminately, regardless of evacuation. There is always the risk of an accident because integral shutters are applied mainly to corridors, passages, and stairs of schools This study evaluated the problem of integral shutter's entrance, evacuation, construction management, and maintenance control through a fire shutter accident case, including present condition of fire shutter installed at school of Okgil, Bucheon and Dongtan, Hwaseong. The results suggest that emergency lighting or signs for passage be set up to check location of entrance easily and install obstruction sensors at fire shutter to reduce life damage. In addition, the number of efficiency tests of fire shutters should be increased by running a trial test monthly or weekly to maintain the performance of fire shutter. Schools need to install a fire shutter- applied sprinkler at the entire floor.

• Fire Science and Engineering
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• v.24 no.5
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• pp.50-59
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• 2010

Four fire scenarios, as the cases of fire sizes of 2 MW and 5 MW, and no installation and activation of atrium fire shutter for dormitory building of Daegu 'D college', were developed and fire simulations were run using FDS (ver. 5.5.0) and Pathfinder 2009 programs. By assessing fire and evacuation, the effects of atrium fire shutter and vents on the smoke control of atrium were evaluated and this study also analyzed fire hazard and egress safety for occupants in the dormitory. Fire shutter's preventing smoke transport around atrium was much effective, but smoke layer descended down the design limit of smoke height and kept about 2 m height from the atrium floor in all cases because flow rate through vents was not enough. For the case of 5 MW fire and no fire shutter, fire hazard was higher due to visibility than temperature and allowable egress time to stairwell was short less than 5 seconds for the occupants on the floors of 4F to 7F. For total occupants, egress time out of main doorway was calculated about 136 seconds. It is sure that additional systems improving the performance of smoke control need to be installed for more safe evacuation.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.345-352
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• 1997

We could analyse the fire behavior using the developed software for fire safety assessment in a large space such as atrium. But Korean building law hasn't admitted the result of fire risk assessment in atrium. In the legislation fire resistant wall or shutter must be required between atrium and office rooms, That has obstructed development of building design and fire protection technique in Korea. From this point of view, we made scenarios of fire spread between atrium and office rooms, and then computed fire spread and fire phenomena using FASTLite and Breakl. In this study, we can decide that fire compartmentalization between atrium and office rooms doesn't require in Atrium building if the material and fire protection system were reliable. Consequently, Korean Fire Protection Regulations have to consider in direction of increasing freedom of building.

• Journal of Applied Reliability
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• v.12 no.1
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• pp.35-46
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• 2012

Wood pellet is one of biomass energy fuels, which is produced by compressing woody biomass such as sawdust, planer shavings, and whole-tree removal or tree tops and branches leftover after logging into cylindrical form. Latterly much attention has been paid to wood pellet boiler which is suitable for use at various scales in domestic and industrial furnaces for heat production to replace conventional fossil fuel energy sources since the use of wood pellet that is carbon neutral can alleviate global warming. This study presents the result of developing a high efficiency wood pellet boiler with 55MJ/h capacity. Efficiency has been improved by using a rotating disk burner with a shorter screw feeder. Special attention has been paid to the improvement of the safety of the wood pellet boiler from backfire by adopting a double protecting system composed of a shutter and an air curtain. The result shows that the efficiencies of the wood pellet boiler are 97.2% and 89.2% based on lower and higher heating values, respectively, at 15.1kW of heating output.