• 한국연소학회:학술대회논문집
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• 2013.06a
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• pp.11-12
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• 2013

To investigate the effect of an inner diameter of the extension tube on the self-ignition when high pressurized hydrogen abruptly released through a tube, both experimental and numerical approach are used. The result show that there is a possibility to have successful ignition when the tube diameter is decreased even at the pressure that could not give sustainable flame with a larger diameter tube. Numerical simulation show the flame development inside the tube and weak and stretch flame spout the tube for 10.9 mm tube, whereas strong complete flame has been generated for 3 mm tube.

• Journal of the Korean Society of Safety
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• v.22 no.6
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• pp.41-45
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• 2007

Short circuit and ground fault account for the primary causes of electrical fires. In this research, real-scale experiments were conducted to assess the possibility of electrical fires due to these causes. The experiment conditions were identical with an actual fire accident, in which the power cable was supported by an iron fence. The purposes of this research are to investigate the short circuit caused by wire cutting, the conductivity of the iron fence depending on its coating conditions, and the ground fault of one wire or two wires in an effort to reconstruct the fire accident. The test results show that, owing to the instant operation of circuit breaker in the moment of short circuit or ground fault, the generated ignition energy is far less than necessary to start an ignition. Therefore it is concluded that electrical fire is highly unlikely if the electric system is protected by a circuit breaker with normal functions.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.5
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• pp.751-756
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• 2023

In this study, We investigated a fire case and performed an experiment to prevent fire from sparks that is generated during grinding operation. Before conduct the test, confirmed that the generating mechanism of fire-flakes in working grinder and the fire experiment was conducted using commonly tools, flammable materials in industrial field. in result, It could be measured scattering distance, temperature, ignition possibility by type of combustible materials. Based on the results of this study, We are expected to be used as basic data for fire prevention in grinding Industry.

• Congress of the korean instutite of fire investigation
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• 2011.04a
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• pp.102-116
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• 2011

With the spread of FMD and AI in the country livestock farmers have used lime(CaO) prevalently and due to incorrect storage lime served as a fire ignition source in a number of cases. As combined chemically with water, lime has exothermic reaction. Then In these experiments we want to know how exothermic reaction - caused by lime - acts as sources of fire ignition in any circumstances and conditions. So we have done experimental work of ignition temperature and ignition process in the artificial conditions as lime combined chemically with water. As a result, we have confirmed that lime could be flammable material sufficiently as a fire ignition source with the proper presence of heat and moisture conditions. If the lime served as sources of fire ignition, as identification techniques of fire scene, we must ascertain the existence of water, flammable material and Calcium Hydroxide($Ca(OH)_2$). We should take special precautions in order to prevent fire and educate the safe handling of lime to the manufacturer and agricultural cooperative's joint livestock farmers who product or use lime.

• Fire Science and Engineering
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• v.33 no.2
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• pp.1-8
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• 2019

This study was conducted to investigate the possibility of spontaneous ignition in Butadiene popcorn polymer, which is used as raw material and product in a chemical plant. A component analysis, thermogravimetric analysis, thermal stability analysis, spontaneous ignition point measurement and accelerated velocity calorimetric analysis were performed. As a result of analysis, various kinds of flammable components were measured and thermogravimetric analysis showed a weight loss of 95.6% in air and 89.2% in nitrogen. As a result of the thermal stability analysis, heat generation started at $88^{\circ}C$ in the air atmosphere, and the heat generation rate increased sharply in the vicinity of the natural ignition point ($220^{\circ}C$). The heat generation started at about $70^{\circ}C$ in nitrogen atmosphere, and the two exothermic peak values were observed up to $450^{\circ}C$. As a result of accelerated rate calorimetry, there was no exothermic phenomenon, and the lowest ignition temperature was $211.7^{\circ}C$ as a result of analysis of natural ignition point. Based on the results obtained from the thermal stability evaluation, it is considered that the possibility of inducing the thermal deformation of the column by the heat of reaction is sufficient.

• Journal of the Korean Society of Safety
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• v.29 no.2
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• pp.89-97
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• 2014

This study analyzed various possibilities of flash fire which could occur in a variety of combats, in order to predict that of flash fire of combat system armor using Autodyn program. The possibility was judged by the temperature distribution of fuels, which was caused by the impact of parts of fuel systems through an armor, in the event of getting shot by external ammunition. Diverse variables could affect the possibility of flash fire: external ammunition(Type A: penetration 570 mm, Type B: penetration 410 mm), fuels(Gasoline, Diesel, Kerosene), the thickness of an armor(100, 200, 300, 400, 500 mm), the gap of a fuel tank and an armor(45, 95, 145, 195, 245, 295 mm). As a result, when an armor was 20 mm think, the temperature of 3 fuels ranged like this: Gasoline 372~387 K, Diesel 442~408 K, Kerosene 384~395 K. Although they made a little difference among them, they all didn't reach their ignition points. When an armor was 200 mm think, each fuel reached the maximum temperature, not reaching its ignition points as well. The thicker an armor was, the lower the temperature got. When Type B ammunition was used, the temperature of fuels went up 19~59 K higher than Type A was used. In the case that the gap of fuel tank and an armor was 20 mm thick, the temperature distribution of Gasoline showed 389~450 K, the maximum temperature appeared in the gap of 145 mm, and the minimum temperature 295 mm. For Type B, the temperature distribution of fuels ranged 386~401 K, the maximum temperature appeared in the gap of 245 mm, and the minimum temperature 45 mm. There was no significant difference between two cases, and neither of them reached its ignition point. Accordingly, as the tested fuels of combat systems didn't reach their ignition points, it is thought that the possibility of flash point of an armor is low.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.202-205
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• 2010

Auto ignition of hybrid rocket using $N_2O$ catalytic decomposition was studied in the present study. The hybrid rocket consists of catalytic igniter, solid fuel, combustor, and nozzle. The Ru/$Al_2O_3$ catalyst for $N_2O$ decomposition was synthesized by an impregnation method, and $N_2O$ conversion as reaction temperatures was measured. The temperature change of the catalytic ignitor was measured at the operating condition, and the possibility for the auto ignition of hybrid rocket was validated.

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.6
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• pp.573-579
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• 2013

Hydrogen engine with homogeneous charged compression ignition can achieve high efficiency by high compression ratio and rapid chemical reaction rates spatially. However, it needs to expansion of the operation range with over-all load conditions which is very narrow due to extremely high pressure rise rate. The adoption of the lean boosting in a HCCI $H_2$ engine is expected to be effective in expansion of operation range since minimum compression ratio for spontaneous ignition is decreased by low temperature combustion and increased surround in-cylinder pressure. In order to grasp its possibility by using lean boosting in the HCCI $H_2$ engine, compression ratio required for spontaneous ignition, expansion degree of the operation range and over-all engine performance are experimentally analyzed with the boosting pressure and supply energy. As the results, it is found that minimum compression ratio for spontaneous ignition is down to the compression ratio(${\varepsilon}$=19) of conventional diesel engine due to decreased self-ignition temperature, and operation range is extended to 170% in term of the equivalence ratio and 12 times in term of the supply energy than that of naturally aspirated type. Though indicated thermal efficiency is decreased by reduced compression ratio, it is over at least 46%.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.461-468
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• 2022

This study is focused on the ignition of ceiling insulation depending on working condition of Sprinkler head in underground parking lot fire. When temperature changes of same point were measured depending on sprinkler's working condition, in Scenario 1, inner temperature at border of spray applied material(SP-2) of ceiling part near the fire and ceiling insulation(blowing polystyrene) was 658.27℃ and its which inner maximum temperature is higher than 427℃ which is the ignition point of ceiling insulation(blowing polistyrene), so it was observed that flame is ignited on the ceiling insulation and spread fire. In scenario 2, Inner fire temperature at border of spray applied material(SP-2) and ceiling insulation(blowing polystyrene) near the fire was 53.10℃ and it was lower than ignition point so it was observed that flame was not ignated on the ceiling insulation. As a result, it was foreseen that possibility of ignition on the ceiling insulation depending on working condition of sprinkler.

• Journal of the Korean Society of Propulsion Engineers
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• v.25 no.6
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• pp.60-65
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• 2021

In this paper, we examined the ignition possibility of the propellant depending on its non-uniform composition of aluminum. Impact and friction sensitivity was investigated by arbitrarily changing the aluminum content in the range of 14~20% to simulate the non-uniform distribution of aluminum in the propellant. As a result of measuring the impact sensitivity, the 50% ignition energy and minimum ignition energy have values around 50 J regardless of the aluminum content. This means that the propellant does not become sensitive to impact even if the aluminum content is increased. On the other hand, the friction sensitivity result shows that as the aluminum content increases, the 50% ignition force and minimum ignition forces were decreased, and thus the propellant becomes sensitive. "Hot Spot" model of propellant ignition is applied, the space inside the propellant is momentarily compressed and ignited by friction stimuli rather than by impact stimuli.