• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.77-84
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• 1997

Cone calorimeter measurements can be used for the calculation of effective material properties, which can be used as input parameters in modeling of fire. Main parameter measured in Cone calorimeter is heat release rate. Some other parameters as time to ignition, effective heat of combustion, mass loss rate or total heat released is also measured in Cone calorimeter. Total heat released is important from the point of view of total energy available in material in Fire situation. Cone calorimeter. measurements were done on several wood species (oak, beech, spruce, poplar). Measurements were provided at external irradiances 30, 50 and 65 ㎾/$m_2$ in horizontal orientation. Heat release rate data were evaluated and compared as a function of external irradiance for various species of wood. furthermore the influence of external irradiance on effective heat of combustion and total heat release was also evaluated for the period of flame combustion.

• Journal of the Korean Society of Safety
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• v.32 no.5
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• pp.20-24
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• 2017

In this study, we have performed the Cone Calorimeter test in accordance with ISO 5660-1 to check the combustion characteristics of building flooring materials. The fire risk of these materials were evaluated by construction code, KFI criteria and standards of flame retardant performance. When samples exposed to external heat flux, all samples consumed a lot of Oxygen for a long time. So heat release from sample burning continued so long. And also all samples produced so much smoke. Even though a few samples were satisfied with only peak heat release rate criteria, all 8 samples were not satisfied with criteria of peak heat release rate and total heat released together. The results of 5 min total heat released were $15.9MJ/m^2{\sim}5.9MJ/m^2$. It menas the results are more than 2~6 times higher than the criteria. The results of 10 min total heat released were $30.1MJ/m^2{\sim}100.8MJ/m^2$. It means the results are more than 3~12 times higher than the criteria. 6 of 8 samples were not satisfied with Dm.corr.(corrected maximum smoke density) criteria. The building flooring materials which we used for this test ignited very fast and the burning continued so long. It means these samples are susceptible to fire.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.70-76
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• 2005

The interior materials of the urban subway car in operation are now being changed to new materials that meet the latest law in effect, the fire safety criteria of the urban railway vehicle. It was well known fact that the composite materials, that were applied to last subway car, were weak on the fire. Contrary to this materials, materials in work have good resistance to the fire. On the paper, To investigate the difference of fire safety level on the subway car, cone calorimeter was used to measure the heat release rate and total heat released according to the ISO 5660. A high radiative heat flux of 50kW/m2 was used to burn out all materials and to simulate the condition of fully developed fire case in the tests.

• Fire Science and Engineering
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• v.24 no.5
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• pp.115-121
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• 2010

This study was performed to test the combustive properties of Pinus rigida-based materials by the treatment of ammonium salts. Pinus rigida plate was soaked in three 20 wt% ammonium salt solutions such as ammonium sulfate (AMSF), monoammonium phosphate (MAPP), and diammonium phosphate (DAPP), respectively, at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). Comparing with virgin pinus rigida plate, specimens treated with the ammonium salts had lower combustive properties and It is supposed that the combustion-retardation properties improved due to the treated ammonium salts in the virgin Pinus rigida. Also, the specimens with treated ammonium salts showed both the lower peak heat release rate (PHRR) and lower total heat release (THR) than those of virgin plate.

• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.96-103
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• 2009

This study was fulfilled to investigate the forest fire risk of forest fuels based on the combustion characteristics of living leaves of coniferous trees and broadleaf trees naturally growing in Youngdong areas of Gangwon Province by using cone calorimeter and smoke density chamber. According to the result, Pinus densiflora and Pinus rigida among coniferous trees released a greater amount of heat release than other kinds. The total smoke release varied depending on the species, whereas Pinus koraiensis showed the largest amount of smoke release. With regard to maximum smoke density, it was much higher in coniferous trees than in broadleaf trees. With regard to smoke temperature, Pinus densiflora showed the lowest compared to other kinds up until 200s from the ignition, but all most trees uniformly maintained constant temperature of about $70^{\circ}C$ after 200s. The concentrations of CO and $CO_2$ release were drastically increased at about 150s and then gradually decreased thereafter. Pinus densiflora showed a bit higher CO release than broadleaf trees, but there was no distinct difference in $CO_2$ release among tress.

• Journal of the Korean Society of Safety
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• v.28 no.3
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• pp.39-43
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• 2013

The present study has been conducted to investigate the fire combustion properties and fire behavior of an IEEE-383 qualified flame retardant cable. The reference reaction rate and reference temperature which are commonly used in pyrolysis model of fire propagation process was obtained by the thermo-gravimetric analysis of the cable component materials. The mass fraction of FR-PVC sheath abruptly decreased near temperature range of $250{\sim}260^{\circ}C$ and its maximum reaction rate was about $2.58{\times}10^{-3}$[1/s]. For the XLPE insulation of the cable, the temperature causing maximum mass fraction change was ranged about $380{\sim}390^{\circ}C$ and it has reached to the maximum reaction rate of $5.10{\times}10^{-3}$[1/s]. The flame retardant cable was burned by a pilot flame meker buner and the burning behavior of the cable was observed during the fire test. Heat release rate of the flame retardant cable was measured by a laboratory scale oxygen consumption calorimeter and the mass loss rate of the cable was calculated by the measured cable mass during the burning test. The representative value of the effective heat of combustion was evaluated by the total released energy integrated by the measured heat release rate and burned mass. This study can contribute to study the electric cable fire and provide the pyrolysis properties for the computational modeling.

• Advances in nano research
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• v.16 no.2
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• pp.127-140
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• 2024

Upon direct/indirect exposure to flame or heat, composite structures may burn or thermally buckle. This issue becomes more important in the natural fiber-based composite structures with higher flammability and lower mechanical properties. The main goal of the present study was to obtain an optimal eco-friendly composite system with low flammability and high thermal buckling resistance. The studied composite consisted of polypropylene (PP) and short abaca fiber (AF) with eggshell powder (ESP) and halloysite clay nanotubes (HNTs) additives. An optimal base composite, consisting of 30 wt.% AF and 70 wt.% PP, abbreviated as OAP, was initially introduced based on burning rate (BR) and the Young's modulus determined by horizontal burning test (HBT) and tensile test, respectively. The effects of adding ESP to the base composite were then investigated with the same experimental tests. The results indicated that though the BR significantly decreased with the increase of ESP content up to 6 wt.%, it had a very destructive influence on the stiffness of the composite. To compensate for the damaging effect of ESP, small amount of HNT was used. The performance of OAP composite with 6 wt.% ESP and 3 wt.% HNT (OAPEH) was explored by conducting HBT, cone calorimeter test (CCT) and tensile test. The experimental results indicated a 9~23 % reduction in almost all flammability parameters such as heat release rate (HRR), total heat released (THR), maximum average rate of heat emission (MARHE), total smoke released (TSR), total smoke production (TSP), and mass loss (ML) during combustion. Furthermore, the combination of 6 wt.% ESP and 3 wt.% HNT reduced the stiffness of OAP to an insignificant amount by maximum 3%. Moreover, the char residue analysis revealed the distinct differences in the formation of char between AF/PP and AF/PP/ESP/HNT composites. Afterward, dilatometry test was carried out to examine the coefficient of thermal expansion (CTE) of OAP and OAPEH samples. The obtained results showed that the CTE of OAPEH composite was about 18% less than that of OAP. Finally, a theoretical model was used based on first-order shear deformation theory (FSDT) to predict the critical bucking temperatures of the OAP and OAPEH composite plates. It was shown that in the absence of mechanical load, the critical buckling temperatures of OAPEH composite plates were higher than those of OAP composites, such that the difference between the buckling temperatures increased with the increase of thickness. On the contrary, the positive effect of CTE reduction on the buckling temperature decreased by raising the axial compressive mechanical load on the composite plates which can be assigned to the reduction of stiffness after the incorporation of ESP. The results of present study generally stated that a suitable combination of AF, PP, ESP, and HNT can result in a relatively optimal and environmentally friendly composite with proper flame and thermal buckling resistance with no significant decline in the stiffness.

• Journal of Mechanical Science and Technology
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• v.18 no.3
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• pp.407-418
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• 2004

Prandtl-Meyer expansion flow with homogeneous condensation is investigated experimentally and by numerical computations. The steady and unsteady periodic behaviors of the diabatic shock wave due to the latent heat released by condensation are considered with a view of technical application to the condensing flow through steam turbine blade passages. A passive control method using a porous wall and cavity underneath is applied to control the diabatic shock wave. Two-dimensional, compressible Navier-Stokes with the nucleation rate equation are numerically solved using a third-order TVD (Total Variation Diminishing) finite difference scheme. The computational results reproduce the measured static pressure distributions in passive and no passive Prandtl-Meyer expansion flows with condensation. From both the experimental and computational results, it is found that the magnitude of steady diabatic shock wave can be considerably reduced by the present passive control method. For no passive control, it is found that the diabatic shock wave due to the heat released by condensation oscillates periodically with a frequency of 2.40㎑. This unsteady periodic motion of the diabatic shock wave can be completely suppressed using the present passive control method.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.3
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• pp.284-288
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• 2005

Baker's yeast was disrupted in a 1.4-L stainless steel horizontal bead mill under a continuous recycle mode using 0.3 mm diameter zirconia beads as abrasive. A single pass in continuous mode bead mill operation liberates half of the maximally released protein. The maximum total protein release can only be achieved after passaging the cells 5 times through the disruption chamber. The degree of cell disruption was increased with the increase in feeding rate, but the total protein release was highest at the middle range of feeding rate (45 L/h). The total protein release was increased with an increase in biomass concentration from 10 to $50\%$(w/v). However, higher heat dissipation as a result of high viscosity of concentrated biomass led to the denaturation of labile protein such as glucose 6-phosphate dehydrogenase (G6PDH). As a result the highest specific activity of G6PDH was achieved at biomass concentration of $20\%$(ww/v). Generally, the degree of cell disruption and total protein released were increased with an increase in impeller tip speed, but the specific activity of G6PDH was decreased substantially at higher impeller tip speed (14 m/s). Both the degree of cell disruption and total protein release increased, as the bead loading increased from 75 to $85\% (v/v)$. Hence, in order to obtain a higher yield of labile protein such as G6PDH, the yeast cell should not be disrupted at biomass concentration and impeller tip speed higher than $20\%(w/v)$ and 10 m/s, respectively.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.768-776
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• 2015

This study was performed to understand combustion properties four major Indonesian wood species such as Albizia, Gmelina, Mangium and Mindi were investigated by cone-calorimeter for better utilization of theses wood species. Heat release rate (HRR), total heat release (TSR), specific mass loss rate (SMLR), effective heat of combustion (EHC), time to ignition (TTI), flame time (FT), specific extinction area (SEA), smoke production rate (SPR) and CO compound production rate were measured. HRR, THR and FT were proportional to the density of woods. Albizia showed the highest HRR, while Mindi had the lowest HRR. For SPR, Albizia showed the highest value due to its higher SEA. On the other hand, Mindi had the lowest SPR due to a lower SEA value. The highest smoke emission was for Albizia at the beginning of combustion. After 300 seconds, smoke emission of Gmleina and Mangium was increased greatly. Mangium and Mindi showed the highest total carbon dioxide emission. Expecially, Gmelina released the highest carbon monoxide during the combustion period and presented three times higher $CO/CO_2$ ratio than those of other species due to incomplete combustion.