• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2001.11a
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• pp.61-66
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• 2001

가스 공정에서 취급하는 가연성물질의 연소 특성 파악은 공정의 안전 확보에 가장 중요한 문제이다. 따라서 연소특성들은 가연성물질이 공정의 취급상 부주의로 인해 누출되어 주위에 공기와 혼합되면 화재 및 폭발이 발생할 수 있는 잠재적 위험성을 평가할 수 있다. 연소특성들로는 폭발한계, 인화점, 최소자연발화점, 최소산소농도, 최소발화에너지, 연소열 등을 들 수 있다/sup 1)/.(중략)

• Explosives and Blasting
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• v.28 no.1
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• pp.55-62
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• 2010

Explosive welding was planed in a closed drift of a mine for its reuse. In this study, we analyzed the stabilization of roof and pillar which were expected to be affected by overpressure experienced during the continual explosive welding. Three equations, normal equation, CONWEP and DDESB, were used for the estimation of overpressure. The investigation shows that the continual use of the explosive welding in a drift may result in considerable damage on the drift.

• Explosives and Blasting
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• v.24 no.2
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• pp.23-31
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• 2006

Optimum additive which gets Possible detonation sensitivity and minimum stability has been selected among several additives. It is able to mitigate a chemical reaction without destroying a structure of emulsion. Kinecker has been developed by mixing both matrix and selected additive through a perfect formulation. The detonation pressure is reduced by 40.66%(47.27% by Nitro Dyne's program), and hole pressure by 33.25% and even VOD by 52.88% against currently used emulsion explosives.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2022.10a
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• pp.99-100
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• 2022

화학산업이 발전함에 따라 잠재적인 화학물질 폭발사고 위험 또한 증가하고 있다. 순식간에 치명적인 인명, 재산피해를 남기는 폭발에 대한 영향을 예측, 분석하기 위해 다양한 해석모델이 활용되고 있지만, 폭발의 물리적 특성상 다양한 형태의 건물이 밀집된 지역에 대해서는 해석모델 사용만으로 높은 정확도의 분석을 진행하기에는 어려움이 있다. 따라서 본 연구는 GIS 공간정보와 3D 폭발 시뮬레이션의 약결합 방식을 적용하였다. 실제 연구지역과 동일한 환경을 구현하여 시뮬레이션을 구동하였고 이에 따른 폭발 규모와 폭발에 노출된 대상별 가해지는 압력 값을 도출하였다. TNT를 기준으로 위험물 저장 및 취급시설에 대한 최저 기준인 지정수량 200kg을 적용하였음에도 최대 2,960kPa의 압력이 발생하는 것으로 확인되었다. 본 연구로 도출된 결과에 건축물의 용도와 중요도를 적용한다면 토지이용계획 및 공간활용에 반영할 수 있으며, 안전관리자로 하여금 리스크 평가, BC분석, 안전관리계획 수립 등에 활용 가능하다고 사료된다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.11
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• pp.1483-1491
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• 2001

Enhancement of pulsed-laser ablation by an artificially deposited liquid film is presented. Measurements of ablation rate, ablation threshold, and surface topography arc performed. Correlation between material ablation and photoacoustic effect is examined by the optical beam deflection method. The dependence of ablation rate on liquid-film thickness and chemical composition is also examined. The results indicate that photomechanical effect in the phase explosion of liquid is responsible for the enhanced ablation. The low critical temperature of liquid induces explosive vaporization with localized photoacoustic excitation in the superheat limit and increases the ablation efficiency. Experiments were carried out utilizing a Q-swiched Nd:YAG laser at near-threshold laser fluences with negligible plasma effect (up to ∼100 MW/cm$^2$).

• Journal of the Korean Institute of Gas
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• v.14 no.3
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• pp.14-20
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• 2010

This paper was studied on the explosion hazard by spark discharge of the lithium-ion battery. The experimental samples were chosen lithium-ion battery(general, notebook) which were used for source of portable equipment. The IEC(International Electrotechnical Commission) type spark ignition test apparatus and experimental gases such as methane, propane, ethylene or hydrogen were used for explosiveness test. It was confirmed through the experiment that the explosion hazard by spark discharge. Also, it was used thermal imager for confirm that spontaneous ignition possibility by short-circuit. As the result, this paper verified that lithium-ion battery should be used and designed by special attention safety in the hazardous zone which is existed explosiveness gas.

• Nuclear Engineering and Technology
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• v.28 no.2
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• pp.103-117
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• 1996

A mathematical model of vapor explosion propagation is presented. The model predict two-dimensional, transient flow fields and energies of the four fluid phases of melt drop, fragmented debris, liquid coolant and vapor coolant by solving a set of governing equations with the relevant constitutive relations. These relations include melt fragmentation, coolant-phase-change, and heat and momentum exchange models. To allow thermodynamic non-equilibrium between the coolant liquid and vapor, an equation of state for oater is uniquely formulated. A multiphase code, TRACER, has been developed based on this mathematical formulation. A set of base calculations for tin/water explosions show that the model predicts the explosion propagation speed and peak pressure in a reasonable degree although the quantitative agreement relies strongly on the parameters in the constitutive relations. A set of calculations for sensitivity studies on these parameters have identified the important initial conditions and relations. These are melt fragmentation rate, momentum exchange function, heat transfer function and coolant phase change model as well as local vapor fractions and fuel fractions.

• Journal of the Korean earth science society
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• v.41 no.5
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• pp.478-489
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• 2020

This study presents an analysis of infrasonic signals from two accidental explosions in Gwangyang city, Jeonnam Province, Korea, on December 24, 2019, recorded at 12 infrasound stations located 151-435 km away. Infrasound propagation refracted at an altitude of ~40 km owing to higher stratospheric wind in the NNW direction, resulting in favorable detection at stations in that direction. However, tropospheric phases were observed at stations located in the NE and E directions from the explosion site because of the strong west wind jet formed at ~10 km. The transmission losses on the propagation path were calculated using the effective sound velocity structure and parabolic equation modeling. Based on the losses, the observed signal amplitudes were corrected, and overpressures were estimated at the reference distance. From the overpressures, the source energy was evaluated through the overpressure-explosive charge relationship. The two explosions were found to have energies equivalent to 14 and 65 kg TNT, respectively. At the first explosion, a flying fragment forced by an explosive shock wave was observed in the air. The energy causing the flying fragment was estimated to be equivalent to 49 kg or less of TNT, obtained from the relationship between the fragment motion and overpressure. Our infrasound propagation modeling is available to constrain the source energy for remote explosions. To enhance the confidence in energy estimations, further studies are required to reflect the uncertainty of the atmospheric structure models on the estimations and to verify the relationships by various ground truth explosions.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.05a
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• pp.91-94
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• 1997

반도체의 생산공정은 생산제품의 특성상 많은 종류의 위험물과 가스를 이용하는 것이 보통이지만, 자동화가 이루어진 대부분의 작업공정과는 달리, 작업자에 의해 직접 이루어지는 것이 보통이다. 이때 작업자의 사소한 실수나 과오로 인해 일단 누출등의 사고가 발생하면, 취급물질 자체의 위험성으로 인해 인명 피해, 화재 및 폭발 둥의 2차 대형재해를 초래할 수 있기 때문에, 반도체공장의 어느 누구도 그 위험성에 대해 과소평가하지 않는 것이 현실이다. (중략)

• Explosives and Blasting
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• v.20 no.1
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• pp.61-66
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• 2002

화약의 힘을 결정하는 요인은 폭속, 가스량, 폭발열등이 있다. 이중 폭속은 화약의 힘을 결정하는 중요한 요인이다. 이러한 폭속을 결정하는 조건은 화약내 구성성분에 따라서 달라진다. 그러나 동일한 화약조성일 경우 폭발속도는 공기중과 같은 개방상태, 천공 내와 같은 밀폐상태에서 차이가 있을 것이며, 또한 이론상 약경, 장전밀도, 뇌관의 위력, 장전방법 등에 의해 지배를 받는다고 알려져 있다. 이에 본 연구에서는 국내 산업용화약류를 대상으로 상기의 조건들을 달리하여 폭속을 측정하고, 그 결과를 바탕으로 실제 폭약의 폭속에 영향을 미치는 조건을 찾아내고 이러한 조건의 변화에 따라 폭속이 어떻게 변화는 지를 알아보고자 한다.