• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2604-2612
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• 2023

Spent nuclear fuel and long-lived radioactive waste must be carefully handled before disposing them off to a geological repository. After the pre-storage period in water pools, spent nuclear fuel is stored in casks, which are widely used for interim storage. Interim storage in casks is very important part in the whole cycle of nuclear energy generation. This paper presents the results of the numerical study that was performed to evaluate the thermal behavior of a metal-concrete CONSTOR RBMK-1500 cask loaded with spent nuclear fuel and placed in an open type interim storage facility which is under fire conditions (steady-state, fire, post-fire). The modelling was performed using the ANSYS Fluent code. Also, a local sensitivity analysis of thermal parameters on temperature variation was performed. The analysis demonstrated that the maximum increase in the fuel load temperatures is about 10 ℃ and 8 ℃ for 30 min 800 ℃ and 60 min 600 ℃ fires respectively. Therefore, during the fire and the post-fire periods, the fuel load temperatures did not exceed the 300 ℃ limiting temperature set for an RBMK SNF cladding for long-term storage. This ensures that fire accident does not cause overheating of fuel rods in a cask.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.4
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• pp.366-371
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• 2009

The authors have published several technical reports on the deterioration of conductor due to forest fire in series so far. This is because even we have been experiencing hundreds of forest fires every year, no systematic research on conductor which is very vulnerable to fire have been fulfilled. This paper describes the sag-tension behavior of conductor under loading current normally when only partial area of a long conductor is exposed to fire. Temperatures of Overhead Conductor were different with measurement position. When the partial area of conductor was heated up to $500^{\circ}C$, 20 % of permanent tension loss was observed. This results in the increase of sag of 1.5 m when span is 300 m. The other results will be presented in the text.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.6 no.3
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• pp.267-281
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• 1994

The Combustion gas behavior induced by fire in a building is numerically investigated. The typical building for this analysis is partially divided by a vertical baffle projecting from the ceiling. The solution procedure includes the low Reynolds number ${\kappa}-{\varepsilon}$ model for the turbulent flow and the discrete ordinates method is used for the calculation of radiative heat transfer equation. The effects of the location and size of fire source and baffle length on velocity and temperature distributions, species mass fraction and flame location are analyzed. As the results of this study, it is found that the case when the fire source is located at the vertical wall is more dangerous than at the bottom wall in view of the combustion products and flame location. It is also found that the radiation effect cannot be neglected in analyzing the building in fire.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.103-104
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• 2013

As a result of experimenting 6 loading combustibles in domestic residential facilities by using Furniture Calorimeter, values of 2,391.26kW were appeared from sofas, 1,891.80kW from drawers, 1,778.95kW from mattress, 1,104kW from chairs, 291kW from tables, and 135.09kW from TV. Also, if applying α value of fire growing rate by classifying fire- growing speeds at NFPA 72 (National Fire Alarm Code 2007, Annex B), mattress can be defined as Ultra-Fast, sofa and drawers Fast, TV Slow, tables Slow, and chairs Medium.

• Journal of Korean Tunnelling and Underground Space Association
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• v.10 no.4
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• pp.313-327
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• 2008

Thermo-mechanical coupled behavior of an underground structure during a fire accident have not been fully understood yet. Moreover, when such a thermo-mechanical coupled behavior is not considered in numerical analyses based on conventional heat transfer theory, fire-induced damage zone in an underground structure can be considerably underestimated. This study aims to develop a FEM-based numerical technique to simulate the thermo-mechanical coupled behavior of an underground structure in a fire accident. Especially, an element elimination model is newly proposed to simulate fire-induced structural loss together with a convective boundary condition. In the proposed model, an element where the maximum temperature calculated from heat transfer analysis is over a prescribed critical temperature is eliminated. Then, the proposed numerical technique is verified by comparing numerical results with experimental results from real fire model tests. From a series of parametric studies, the key parameters such as critical temperature, element size and temperature-dependent convection coefficients are optimized for the RABT and the RWS fire scenarios.

• Steel and Composite Structures
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• v.20 no.3
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• pp.651-669
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• 2016

The behavior of shear connectors plays a significant role in maintaining the required strength of a composite beam in normal and hazardous conditions. Various types of shear connectors are available and being utilized in the construction industry according to their use. Channel connectors are a suitable replacement for conventional shear connectors. These connectors have been tested under different types of loading at ambient temperature; however, the behavior of these connectors at elevated temperatures has not been studied. This investigation proposes a numerical analysis approach to estimate the behavior of channel connectors under fire and compare it with the numerical analysis performed in headed stud and Perfobond shear connectors subjected to fire. This paper first reviews the mechanism of various types of shear connectors and then proposes a non-linear thermo-mechanical finite element (FE) model of channel shear connectors embedded in high-strength concrete (HSC) subjected to fire. Initially, an accurate nonlinear FE model of the specimens tested at ambient temperature was developed to investigate the strength of the channel-type connectors embedded in an HSC slab. The outcomes were verified with the experimental study performed on the testing of channel connectors at ambient temperature by Shariati et al. (2012). The FE model at ambient temperature was extended to identify the behavior of channel connectors subjected to fire. A comparative study is performed to evaluate the performance of channel connectors against headed stud and Perfobond shear connectors. The channel connectors were found to be a more economical and easy-to-apply alternative to conventional shear connectors.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.48-50
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• 2013

In this study, Car fire for test using ISO 9705 10MW Large Scale Calorimeter. Especially, study on the underground parking for the fire resistance performance. The underground parking lot of the fire resistance regulations in according to with the standard heating curve in Korea. Because of this burning car through experiments to the propose a new heating curve.

• Journal of the Korean Institute of Gas
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• v.14 no.6
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• pp.31-37
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• 2010

In this study, to propose the analysis method of heat and smoke behavior of fire using the CFD-based fire simulator FDS, comparison of the simulation results against the experimental results and the sensitivity of the results to the grid sizes have been investigated. For the wood fire, thermal images captured from the experiments were compared against the FDS simulations, and the maximum temperatures agreed in~4.3 % error, showing the applicability of FDS in the interpretation of the fire phenomena. In the aspect of the sensitivity to the grid size for the subway fire, FDS results of smoke temperature, CO concentration and visibility converged and showed no distinct changes for the grid size < $28(L){\times}28(W){\times}14(H)$, guaranteeing that the FDS fire model set in this research could interpret the fire phenomena successfully.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.35-43
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• 1997

Fire research is urgently needed so as to mitigate fire damage with moderate costs. A system of fire research consisting of basic research, applied research and development of new technology for fire prevention and protection is being formed in China. A general structure of organizations related to fire research is outlined. Typical research work in the State Key Lab of Fire Science is given as an example of fire research in China including: Field-Zone-Network modeling of building fire, mechanism of boilover, forest fire behavior, computer modeling of fire spread in micsogravity, and duality of fire rules and its application.

• 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.