• Fire Science and Engineering
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• v.18 no.2
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• pp.27-33
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• 2004

An accurate knowledge of the AIT(Autoignition temperatures) of chemicals is important in developing appropriate prevention and control measures in industrial fire protection. The AITs describe the minimum temperature to which a substance must be heated, without the application of a flame or spark, which will cause that substance to ignite. The measurement AITs are dependent upon many factors. namely initial temperature. pressure, volume, fuel/air stoichiometry. catalyst material, concentration of vapor, ignition delay time. This study measured the AITs of acids from ignition delay time by using ASTM E659-78 apparatus which was produced in the year 1994. The experiment AITs were a good agreement with the calculated AITs by the proposed equations with a few A.A.P.E.(average absolute percent error) and A.A.D.(average absolute deviation).

• Journal of the Korean Society of Safety
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• v.10 no.2
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• pp.84-91
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• 1995

The characteristics of critical spontaneous ignition of granulated activated carbon were investigated In atmospheres of differing oxygen concentration. At the same concentration the larger vessels yielded the lower critical spontaneous ignition temperature. At the same vessel, as the concentration of oxygen was reduced, Ignition occurred later and at higher ambient temperature, and critical spontaneous ignition temperature increased. The apparent activation energy calculated from the Frank-Kamenetskii's ignition theory appeared to be the slight different value respectively and the mean apparent activation energy was 19850㎈/㏖.

• 한국연소학회:학술대회논문집
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• 2002.11a
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• pp.193-207
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• 2002

The present study is mainly motivated to investigate the vaporization, autoignition, and combustion of liquid fuel spray injected into high pressure environment. In order to represent these phenomena realistically, discrete droplet model (DDM) which simulates the spray using finite number of representative droplets was adopted for detailed consideration of the finite rate of uansport between liquid and gas phases. The Eulerian-Lagrangian formulation was used to analyze the two-phase interactions. The high pressure vaporization model was applied using the thermodynamic and phase equilibrium at droplet surface. The high pressure effect as well as high temperature effect was considered in the calculation of liquid and gas properties. The characteristics of spray in high pressure environment were explained by comparison with normal pressure case.

• Fire Science and Engineering
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• v.25 no.6
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• pp.184-189
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• 2011

This study measured the AITs of n-butanol + n-decane system from ignition delay time (time lag) by using ASTM E659 apparatus. The AITs of n-butanol and n-decane which constituted binary system were $340^{\circ}C$ and $212^{\circ}C$, respectively. The experimental AITs of n-butanol + n-decane system were a good agreement with the calculated AITs by the proposed equations with a few A.A.D. (average absolute deviation).

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.265-266
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• 2015

The multi-environment PDF model coupled with flamelet generated manifolds(FGM) has been developed for a large eddy simulation of turbulent partially premixed lifted flame. This approach has a capability to realistically account for the transport and evolution of probability density function for mixture fraction and progress variable with the manageable computational burden. Using the tabulated chemistry, it is possible to track radical distributions which is important to predict autoignition process with the vitiated coflow environment. Numerical results indicate that the present yields the good agreement with experimental data in terms of mixture fraction, temperature, and species mass fractions.

• Proceedings of the Safety Management and Science Conference
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• 2001.05a
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• pp.301-310
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• 2001

A study for the dangerous properties measurment of dust explosion was attended by the various dust concentration on Anthraquinone, Sodiumbenzoic acid, Corn starch, soy sauce powder, and cheese powder. As the result, maximum explosion pressure, the maximum rate of pressure rise, autoigntion temperature, and the water content of dust on lower limit explosion concentration was obtained as follows 1. The lower limit explosion concentration on soy sauce powder with the humidity of 65 to 90% increased by increasing the con tent of moisture, and the effect of dry air and moisture air decreased better in make of dry air. 2. The effect of a various dust concentration on autoigntion temperatures is investigated, If the vessel of dust explosion is small size and the easiness of autoignition was controled by air within the vessel, because it was better decreased air with increasing of dust concentration 3. The maximum explosion pressures of Anthraguinone, sodiumbenzoic acid, com starch, soy sauce powder, and cheese powder were 1.0g/$\ell$, 1.0g/$\ell$, 1.5g/$\ell$, 1.5g/$\ell$, and 1.5g/$\ell$, respectively, and the maximum rate of pressure rise were 0.5g/$\ell$, 0.5g/$\ell$, 1.0g/$\ell$, 1.0g/$\ell$, and 1.0g/$\ell$, respectively.

• Journal of the Korean Society of Safety
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• v.31 no.5
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• pp.42-48
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• 2016

The usage of the correct combustion properties of the treated substance for the safety of the process is critical. For the safe handling of n-nonane being used in various ways in the chemical industry, the flash point and the autoignition temperature(AIT) of n-nonane was experimented. And, the explosion limit of n-nonane was calculated by using the flash point obtained in the experiment. The flash points of n-nonane by using the Setaflash and Pensky-Martens closed-cup testers measured $31^{\circ}C$ and $34^{\circ}C$, respectively. The flash points of n-nonane by using the Tag and Cleveland open cup testers are measured $37^{\circ}C$ and $42^{\circ}C$. The AIT of n-nonane by ASTM 659E tester was measured as $210^{\circ}C$. The lower explosion limit by the measured flash point $31^{\circ}C$ was calculated as 0.87 vol%. And the upper explosion limit by the measured upper flash point $53^{\circ}C$ was calculated as 2.78 vol%. It was possible to predict lower explosion limit by using the experimental flash point or flash point in the literature.

• Journal of the Korean Society of Safety
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• v.32 no.5
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• pp.25-31
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• 2017

The flash point, explosion limits, autoignition temperature(AIT) are important combustible properties which need special concern in the chemical safety process that handle hazardous substances. For the evaluation of the flammable properties of n-butylacetate, this study was investigated the explosion limits of n-butylacetate in the reference data. The flash points, fire points and AIT by the ignition delay time of n-butylacetate were experimented. The lower flash points of n-butylacetate by using the Setaflash and Pensky-Martens closed-cup testers were $24^{\circ}C$ and $26^{\circ}C$, respectively. The flash points of n-butylacetate using the Tag and Cleveland open cup testers are measured $31^{\circ}C$ and $40^{\circ}C$, respectively. And the fire points of n-butylacetate by the Tag and Cleveland open cup testers were measured $32^{\circ}C$ and $41^{\circ}C$. The AIT of n-butylacetate measured by the ASTM 659E tester was measured as $411^{\circ}C$. The lower explosion limit of lower flash point $24^{\circ}C$, which was measured by the Setaflash tester, was calculated to be 1.40 vol%. Also, the upper explosion limit of upper flash point $67^{\circ}C$ the Setaflash tester was calculated to be 12.5 vol%.

• Journal of the Korean Society of Safety
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• v.7 no.4
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• pp.45-53
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• 1992

Sponataneous ignition characteristics for granulated activated carbon were observed by performing experiments at constant ambient temperature and varying the ambient temperature sinusoidally. In case of varying the ambient temperature sinusoidally, the amplitudes of temperature were 5$^{\circ}C$, 1$0^{\circ}C$ and 15$^{\circ}C$ respectively, and the period in each amplitude was varied at an interval of 30minutes from zero to 3hours. As the results of experiments at a constant ambient temperature, the critical spontaneous ignition temperature of the sample decreased as the sample vessel size increased. Apparent activation energy of the sample calculated from the Frank-Kamenetskii's thermal Ignition theory was 38.82［kca1/mo1］ In case of varying the ambient temperature sinusoidally, the critical spontaneous ignition tempera-ture was lower than that at the constant ambient temperature, and the minimum critical spontaneous ignition temperature decreased with the amplitude of heating sinusoidal curve. At the same amplitude, the critical spontaneous ignition temperature decreased until it reached the minimum point and then in-creased as the period increased.

• Journal of the Korean Society of Safety
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• v.7 no.1
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• pp.47-56
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• 1992

Spontaneous ignition charactenstics for fish meal were observed by performing experiments at constant ambient temperature and varying the ambient temperature sinusoidally. As the results of the experiments at a constant ambient temperature, the critical spontaneous ignition temperature of the sample for large, intermediate and small vessels was 170.5$^{\circ}C$, 177.5$^{\circ}C$ and 188.5$^{\circ}C$, respectively. The critical spontaneous ignition temperature decreased as the sample vessel size increased. Apparent activation energy of used fish meal calculated from the Frank-Kamenetskii's thermal ignition theory was 37.60Kcal/mol. In case of varying the ambient temperature sinusoidally, the amplitudes of temperature were 1$0^{\circ}C$, 2$0^{\circ}C$ and 3$0^{\circ}C$ respectively with the period in each amplitude 1hr, 2hrs and 3hrs. The results showed that the critical spontaneous ignition temperatures at the varied amplitudes of temperature were lower than that at the constant anbient temperature and increased as the amplitude increased. At the same amplitude, the critical spontaneous ignition temperature increased with the period.