• Elastomers and Composites
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• v.16 no.4
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• pp.211-216
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• 1981

A series of conveyer rubber belts has been made by blending natural rubber(NR), styrene butadiene rubber(SBR), chloroprene rubber(CR) and additives on nylon cords, and their respective flammability has been investigated. It has been observed that: 1. By adding an antiflame agent to the belt, in addition to 70% chlorinated paraffine and antimony oxide($Sb_{2}O_{3}$), the inflammability is improved remarkably to O - 2 seconds due to the synergistic effect, while a sample without antiflame B fails to pass the KS M 6678 test. 2. Physical properties, such as tensile strength, elongation at break and adhesion strength, of the sample belts have been studies by varying ratios of NR/CR from 20 to 100, and it has been observed that the higher ratios have the better physical properties.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.3
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• pp.220-231
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• 1996

In this research, we use IDI type constant volume combustion chamber which may make up stratified combustion to construct the design back data of lean-burn engine. Some experiments are conducted by the passagehole angle in the adapter of main chamber and sub-chamber. The effects on the combustion characteristics according to the ignition timing are investigated. The used fuel is methanol prospective for alternative fuel. Fuel is injected under 10.78MPa using solenoid and accumulator. As the results of the experiment, combustion characteristics reveals that ignition timing, passagehole angle and shape greatly effects on. Lean inflammability limit is extended to 0.45 in equivalence ratio.

• Journal of the Society of Disaster Information
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• v.20 no.2
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• pp.293-301
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• 2024

Purpose: Ministry of Environment statistics reveals more than 132 fire·explosion accidents in South Korea between 2014 and 2023. Among them, fire and/or explosion accidents are very impactive in their scale and consequence. This study aims to suggest a new method of reasonable way to calculate the ventilation rate of indoor facility handling hazardous chemicals based on their inflammability. Method: A new method to calculate the ventilation rate is based on the physicochemical properties of the chemicals handled, which is more reasonable compared with the current regulation based only on the floor area of the facility. Result: Considering the physicochemical properties, 178 chemicals based on their inflammability were studied and 168(94%) met the criteria for the current regulation. Some materials have been shown to require too much or too little ventilation rate. Conclusion: Through this study, a reasonable method of calculating the required ventilation rate was proposed. This should be applied to ensure the safety of workers to deal chemicals.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.3
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• pp.129-139
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• 1995

This study investigates the combustion characteristics of methane-hydrogen-air premixture in a constant volume combustion chamber. Primary factors of the combustion characteristics of methane- hydrogen-air premixture are the equivalence ratio and hydrogen supplement rate. In the case of $\phi$= 1.1, maximum combustion pressure and heat release rate have peaks, and they increase as the initial pressure and hydrogen supplement rate increase. The total burning time is also the shortest at the $\phi$= 1.1, it shorten by lowering the initial pressure and by increasing the hydrogen supplement rate. The maximum flame temperature is shown at the $\phi$= 1.0, and increasing the initial pressure and hydrogen supplement rate, it increases. The concentration of NO reveals the highest value at the $\phi$= 0.9, and it increases by increasing the initial pressure and hydrogen supplement rate. It is also found that the limit of lean inflammability of methane-hydrogen-air premixture is greatly widened by increasing the hydrogen supplement rate.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.1
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• pp.65-75
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• 1995

The present study was investigated combustion characteristics of methane-air mixtures at stratified charge in a constant volume combustion chamber. The results indicated that even the vety lean mixture, which is normally not flammable in single chamber type, could be burned within. a comparatively short time by using sub-chamber with stratified charge method. And the lean inflammability limit of mixture in a main chamber was about ($\phi_m$cr=O.46, when the equivalence ratio of a sub-chamber was $\phi_s$= 1.0. Initial time of pressure increase and total burning times were decreased and maximum combustion pressure. was increased as the equivalence ratio of both sub and main chamber approached unity. Specifically, initial time of pressure increase and total burning times were greatly affected rather by. the equivalence ratio of sub-chamber than that of main chamber. The maximum combustion pressure was little affected if the total equivalence ratio lies in the same range.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.8
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• pp.2022-2029
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• 1995

The experiment was performed by using the condenser discharge ignition device in a constant volume combustion chamber for high pressure, equivalent to the TDC of spark ignition engine, which makes the forced turbulent field possible. The conclusions obtained under various initial pressures, initial temperatures, and turbulent conditions of the methanol-air mixture are as follows : As initial pressure, initial temperature of the mixture, and the ignition energy increase, the inflammability limit expands, but the lean inflammability limit decreases as turbulence intensity increases. Combustion duration is shorter in the case of the lower initial pressure, the higher initial temperature, an equivalence ratio of 1.1-1.2, and even though turbulence intensity increases up to optimum value. Maximum combustion pressure increases in turbulent ambience under the same mixture condition, only in the case each optimum turbulence intensity exists under every condition. As the turbulence intensity increases .tau.$_{10}$ proportion increases while the .tau.$_{pr}$ proportion decreases....

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.273-278
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• 2003

Today's electrical facilities demand improvements from the standpoints of non-inflammability, simple maintenance and inspection, safety and operating rationalization. The molded power with numerous special features that meet these various demands is acclaimed by all users and has a record of numerous applications. Its applications are expected to expend further in the future.

• Fire Science and Engineering
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• v.25 no.3
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• pp.57-62
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• 2011

The combustion characteristic was evaluated for Pinus densiflora, used as a building material in Hanok, which were treated with two different flame retardant method. The specimen was brushed with flame retardant liquid two or three times and then let the specimen dehydrated during 24 h for spreaded treating. And the other specimen was soaked in the liquid for 72 h. The test methods were inflammability test using meker burner and heat release rate test using cone calorimeter. As a result for the tests, flame retardant treated specimens met the requirements of the inflammability and the spreaded treated method was more efficient than immersed method. The spreaded treated specimen had lower combustive properties than immersed specimen in TTI (time to ignition), PHRR (peak heat release rate), MLR (mass loss rate) and THR (total heat release).

• Proceedings of the KIEE Conference
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• 1991.11a
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• pp.296-298
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• 1991

When insulating oil was flowed through a pipe, the electrostatic charge in the oil was increased using inflammability oil, an electrostatic phnomena which may cause significantly problems as explosion must be circumvented by some methods. In this paper, Streaming insulating oil electrificated by streaming electrification of electrification pipe and standing insulating oil were affected under the high field strength, temperature of insulating oil, and concentration of surfactant. The electrical conduction was compared and analysed by these influence.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.129-131
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• 1990

When insulating oil is flowed through a pipe, the electrostatic charge in the oil will be increased. Using inflammability oil, an electrostatic phenomena which may cause significantly problems as explosion must be circumvented by some methods. In this paper we made a new electrode which was applied AC field to the flowing oil for reducing electrostatic charge. Before we developed the new method of an electrostatic elimination, the electrification experiment was performed by using the same electrode which was supplied DC voltage to realize electrified conditions. As a result of this study, the effect of the electrostatic elimination could be observed.