• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.5
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• pp.413-430
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• 2011

Consideration on the explosion resistant design of infrastructure has increased in the recent years. The explosion load is caused by gas explosion or bomb blast. In this study an analytical model is developed, whereby the tunnel structure is divided in several elements that are schematized as single degree of freedom mass-spring-dashpot systems on gas explosion. Using this simple model a sensitivity analysis has been carried out on tunnel structure design parameters such as explosive peak pressure, duration of the load, thickness of structure, burial depth. Finite element method was used to investigate the dynamic response and plastic zone of a tunnel under gas explosion. And it was found from the comparison of the analysis results that there are slight differences in the response of the intermediate wall between the single degree of freedom mass-spring-dashpot model and FEM.

• Journal of Korean Society for Quality Management
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• v.45 no.3
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• pp.533-547
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• 2017

Purpose: This study proposes the main sources of uncertainty and uncertainty analysis of a measurement system of insensitive munitions tests. Methods: We established the mathematical model for calculating measurement uncertainty of insensitive munitions tests, conducted experiments for calculating uncertainties of dynamic sensitivity and overshoot value, and estimated the distributions of uncertainty factors. Results: The measurement uncertainty calculation methods are presented, which include experimental data processing methods for calculating uncertainties of dynamic sensitivity and overshoot value. Conclusion: The measurement of explosion pressure in insensitive munitions tests is an important issue to the reporting test results and classifying reaction types. The more efforts to ensure the reliability of the insensitive munitions tests results are required.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.9
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• pp.1317-1326
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• 2003

The maximum temperature limit at which liquid boils explosively is called the superheat limit of liquids. The superheat limits of hydrocarbon liquids and their mixtures were measured by the droplet explosion technique. Also the fully evaporated droplet at the superheat limit and subsequent bubble evolution from the fully evaporated droplet were visualized. The pressure wave emanating from the evaporating droplet and subsequent bubble evolution process were measured by a piezoelectric transducer.

• KSBB Journal
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• v.4 no.3
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• pp.235-240
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• 1989

A novel pretreatment of rice straw has been developed to increase the reactivity of cellulose, in particular to increase the rate and extent of cellulose enzymatic hydrolysis. This technique is called ammonia-freeze-explosion method and relies on treatment of the lignocellulosic material with a volatile liquid under pressure followed by pressure release to evaporate the liquid and reduce the temperature by Bme E. Dale of Texas A & M University. Volatile liquids which also chemically explosion and swell lignocellulosic materials are particularly effective when used in this technique. Above four times of conversion of cellulose to glucose has been achived by enzymatic hydrolysis of rice straw with this method.

• Journal of the Korean Institute of Gas
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• v.9 no.4 s.29
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• pp.50-56
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• 2005

Liquefied Petroleum 6aso-PG) is combustible gas which used for fuel for domestic and automobiles. A research for adjust a component of LPG to improve the fuel characteristics and control the manufacturing process of that is carrying in petrochemical industry. Some kinds of LPG blending is considered as a adjusting method to control component of LPG. LPG is mainly propane for domestic use and butane for automobile use but propylene and butylene also a kind of LPG Change of explosion characteristic and combustion gas component by mixing of propylene in propane and butane was measured and analysed in this research. Based on the result of experiment, it was found that explosion pressure and pressure rise rate was slightly increased with mixing rate of propylene and it was considered the possibility of increasing the CO concentration in combustion gas with increase the mixing rate of propylene.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.9
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• pp.918-922
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• 2015

As international environmental regulations for pollutant and greenhouse gas emissions discharged from ships are being reinforced, it is drawing attention to use LNG as ship fuel. This paper compares the explosion risk potential in the LNG fuel gas supply systems of two types used in marine LNG fuelled vessels. By selecting 8500 TEU class container ships as target, LNG storage tank was designed and pressure conditions were assumed for the use of each fuel supply type. The leak hole sizes were divided into three categories, and the leak frequencies for each category were estimated. The sizes of the representative leak holes and release rates were estimated. The release rate and the leak frequency showed an inverse relationship. The pump type fuel gas supply system showed high leak frequency, and the pressure type fuel gas supply system showed high release rate. Computational fluid dynamics simulation was applied to perform a comparative analysis of the explosion risk potential of each fuel supply system.

• Journal of the Korean Institute of Gas
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• v.7 no.4 s.21
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• pp.24-29
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• 2003

Numerical analysis was conducted to predict the damage of indoor gas explosion for the propagation of explosion flame. Indoor gas diffusion distribution due to gas leakage was obtained by diffusion equation that adopted initial conditions from reference. Enthalpy of each gas-mixture ratio and reduced mechanism was applied to calculate flame temperature, and laminar combustion velocities with the variant of each gas concentration from reference were applied to the gas mixture. Turbulent combustion velocity was modeled by coupling of turbulent energy and laminar combustion velocity in k-$\epsilon$ model. For the analysis of flame propagation cartesian and cylindrical coordinate were used to indoor position and flame propagation respectively. The study analyzes the cause of pressure rising with the variation of flame propagation by glass damage, and the result shows that indoor pressure rising with ignition position varies window dimension.

• Journal of the Korean Geosynthetics Society
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• v.21 no.3
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• pp.21-27
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• 2022

For carbon neutrality, interest in R&D and infrastructure construction for hydrogen energy, an eco-friendly energy source, is growing worldwide. In particular, for hydrogen stations installed in downtown areas, underground hydrogen infrastructure are being considered to increase a safety distance from hydrogen tank explosions to adjacent structures. In order to design an appropriate location and depth of the underground hydrogen infrastructure, it is necessary to evaluate the impact of the explosion of the underground hydrogen infrastructure on adjacent structures. In this paper, a numerical model was developed to analyze the effect of the underground hydrogen infrastructure explosion on adjacent structures, and the over pressure of the hydrogen tank was evaluated using the equivalent TNT (Trinitrotoluene) model. In addition, parametric analysis was performed to estimate the stability of adjacent structures according to the construction conditions of the underground hydrogen infrastructure.

• Explosives and Blasting
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• v.12 no.3
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• pp.8-16
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• 1994

The primary court house judged that 5th floor's Bldg, structure were inclined 1/150 degree to west-ward by Explosion of Ad, Balloon in the Room. Surveyor made the report to denied the Judgement of primary court. With evidently and Theoritically. but It is waiting the juge of higher court house. Explosion pressure ${\Delta}p$ is as follows $\Delta{p}=4.2100{\times}{\lambda}^{-1.38}=4.2100{\times}{45}^{-1.38}=4.210{\times}{0.00487}=0.02kg/cm^2$.

• Proceedings of the KAIS Fall Conference
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• 2007.05a
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• pp.42-45
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• 2007

This paper is estimation of structure damage caused by VCE(Vapor Cloud Explosion) in enclosure. As we estimate the influence of damage which occur at gas facility in factory. We can utilize it the elementary data of safety distance. In this study, the influence of explosion over-pressure caused by VCE in enclosure was calculated by using the Hopkinson's scaling law and the accident damage was estimated by applying the influence on the adjacent structure into the probit model. As a result of the damage estimation conducted by using the probit model, both the damage possibility of explosion overpressure to structures 20 meters away and that of overpressure to glass bursting 80m meters away showed nothing.