• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.11a
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• pp.172-177
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• 2002

가스폭발 시 폭발 압력에 의해 건물의 일부 또는 전체적인 파괴와 함께 외부에 영향을 미치는 영향은 주로 폭풍파의 압력과 고온의 화염이다. 그 중에서도 폭풍압은 건물에서의 가스폭발 시 파열면을 통과한 급격한 압력 방출에 의해 생겨나는 물리적인 현상으로 그 충격은 때에 따라서 구조물을 붕괴시킬 만큼 크다. 폭발에 의해 발생되는 폭풍압에 의한 피해가 크기 때문에 과거부터 폭풍압에 대한 연구가 계속되어 왔다.(중략)

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.05a
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• pp.433-438
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• 2002

화재 및 폭발 특성치로 인화점, 최소발화온도, 폭발한계, 최소발화에너지, 연소열 등을 들 수 있다 이 가운데 폭발한계(explosive limits)는 가연성물질(가스 및 증기)을 다루는 공정 설계 시 고려해야 할 중요한 변수로써, 발화원이 존재할 때 가연성가스와 공기가 혼합하여 일정 농도범위 내에서만 연소가 이루어지는 혼합범위를 말한다/sup 1)/. 특히 폭발범위는 온도, 압력, 불활성가스의 농도, 화임전과 방향, 용기의 크기, 무리리적 상태 등에 의해 변한다/sup 2)/.(중략)

• Journal of the Korean Institute of Gas
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• v.20 no.1
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• pp.29-39
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• 2016

Electrical apparatuses for use in the presence of explosive gas atmospheres have to be special designed to prevent them from igniting the explosive gas. Flameproof design implies that electrical components producing electrical sparks are contained in enclosures and withstand the maximum pressure of internal gas or vapours. In addition, any gaps in the enclosure wall have to designed in such a way that they will not transmit a gas explosion inside the enclosure to an explosive gas or vapours atmosphere outside it. In this study, we explained some of the most important physical mechanism of Maximum Experimental Safe Gap(MESG) that the jet of combustion products ejected through the flame gap to the external surroundings do not have an energy and temperature large enough to initiate an ignition of external gas or vapours. We measured the MESG and maximum explosion pressure of propane and acetylene by the test method and procedure of IEC 60079-20-1:2010.When the minimum MESG is measured, the concentration of propane, acetylene in the air is higher than the stoichiometric point and their explosion pressure is the highest value.

• Journal of the Korean Institute of Gas
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• v.5 no.2 s.14
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• pp.36-42
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• 2001

A leak of fuel gas in partially confined area creates a flammable atmosphere and give rise to an explosion, which is one of the most common accident in domestic. Observations from accident in domestic suggest that some explosions are caused by a quantify of fuel significantly less than lower explosion limit(LEL) amount required to fill the room, which is attributed to inhomogeneous mixing of leaked gas. The minimum amount of leaked gas for explosion is highly dependent on the mixing degree in the area. For lighter gas, such as methane, a high concentration tends to build up in the space from ceiling of room. But heavy gas, such as propane, a high concentration tends to build up in the space from bottom of room. This paper presents a method for analysing the explosion hazard in a room with very small amount of leaked gas. Based on explosion limit concentration, the gaussian distribution model is used to estimate the minimum amount of leak which yields a specified explosion pressure. The results demonstrate that catastrophic structural damage can be achieved with a volume of fuel gas which is less than 0.5 percent of the total enclosed volume in domestic. The method will help analyzing hazard to develop new safe device as well as investigating accident.

• Journal of the Korean Institute of Gas
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• v.9 no.3 s.28
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• pp.9-14
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• 2005

To estimate the explosion characteristics of converted gas, the study was examined into effects of altering oxygen concentration and adding hydrogen. From the result of the experiment, as the concentration of converted gas and hydrogen were increased at $21\%$ oxygen concentration, the lower explosion limit was low. Minimum explosion oxygen concentration was $6\%$. Maximum explosion pressure of converted gas was $4.61 kg_f/cm^2$, now Maximum explosion pressure rising velocity was $130.75 kg_f/cm^2/s$ at converted gas concentration $40\%$. Also, minimum ignition energy was 0.13 mJ at converted gas concentration $50\%$.

• Explosives and Blasting
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• v.34 no.1
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• pp.1-10
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• 2016

On August 12, 2015, two huge explosions were accidently happened in Tianjin port, China. The explosion energies of the two explosions were similar to those of TNT 3 tons and TNT 21 tons. Until now, the cause of the explosions was not clearly announced but some guesses of the cause were released. One of the possible cause of the explosion is the generation of explosive acetylene gas from the chemical reaction between $CaC_2$ and spraying water to extinguish fire happened at the storage site of different chemical compounds. The explosion of acetylene gas might ignite the explosion of 800 tons of ammonium nitrate. In this study, the explosion due to the scenario was analyzed in order to check that such a chemical reaction can produce the huge explosion observed at the Tianjin accident.

• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.49-55
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• 1997

Destruction phenomena of structure by gas explosion is due to the explosion pressure and heat. Explosion pressure is a kind of energy converted from the gas mixture explosion. In this paper, we tried to find the relationship between explosion characteristics and combustion heat of the hydrocarbon-oxygen mixtures. Experiment were carried out with the volume of $5916cm^3$ cylindrical explosion vessel. Hydrocarbon gases which used in this study were methane, ethylene, propane, and buthane Experimental parameter was the concentration of the gas mixtures. Explosion characteristics were measured with strain type pressure transducer through the digital storage oscilloscope. From the experimental result, it was found that explosion pressure depend upon the combustion heat.

• Journal of the Korean Institute of Gas
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• v.20 no.3
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• pp.30-37
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• 2016

Electrical apparatuses for use in the presence of flammable gas atmospheres have to be specially designed to prevent them from igniting the explosive gas. Flameproof design implies that electrical components producing electrical sparks are contained in enclosures and withstand the maximum pressure of internal gas or vapours. In addition, any gaps in the enclosure wall have to designed in such a way that they will not transmit a gas explosion inside the enclosure to an explosive gas or vapours atmosphere outside it. In this study, we explained some of the most important physical mechanism of MESG(Maximum Experimental Safe Gap) that the jet of combustion products ejected through the flame gap to the external surroundings do not have an energy and temperature large enough to initiate an ignition of external gas or vapours. We measured the MESG and maximum explosion pressure of ternary gas mixtures(propane-acetylene-air) by the test method and procedure of IEC 60079-20-1:2010. As a result, the composition of propane gas that has lower explosive power than acetylene gas in the ternary gas mixtures makes greater effects on MESG and explosion pressure.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.606-611
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• 2018

City natural gas is classified flammable hazardous gas and should be secured according to explosion risk assessment determined by Industrial Standard KS C IEC. In this study, leak size, ventilation grade and effectiveness were adopted to the KS C IEC for risk assessment in natural gas supply system. To evaluate the applicability of the computational fluid dynamics (CFD), the risk assessment was studied for four different conditions using hypothetical volume($V_z$) valuesfrom gas leak experiments, KS C IEC calculation, and CFD simulation.

• Journal of the Korean Institute of Gas
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• v.2 no.2
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• pp.61-69
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• 1998

The risk assessments for gas leak in underground pipeline are conducted about the explosion accident of AHYUN-DONG underground service-base on December, 1994(Gaussian gas, LNG) and the accident of TAEGU subway on April 1995(Heavy gas LPG). We have calculated the total mass of gas release and have respected the efficient of explosions with report of the spot. The dispersion zones of LNG were calculated as large as fifteen times to those of LPG by ALOHA. The effects of thermal radiation from LNG explosion were assumed less than that from LPG by PHAST.