• Title/Summary/Keyword: Vapor cloud explosion

Search Result 56, Processing Time 0.032 seconds

A Development of Expert System for the Estimated Maximum Loss of Vapor Cloud Explosion (증기운 폭발시의 예상최대손실 산정을 위한 전문가 시스템 개발)

  • 김원철
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 1996.11a
    • /
    • pp.37-42
    • /
    • 1996
  • The assessment of catastrophic accidents such as BLEVE, vapor cloud explosion, and toxic material releases in the chemical process industries(CPI) shall be carried out according to the Requirement of PSM/SMS enforced by Korea Government Agencies, but reasonable models are not proposed for the practical application. The traditional models, TNT Equivalency Model, are well-known and helpful for the assessment of vapor cloud explosion. However, the estimated-damage-area using the traditional model has much more deviations comparing to the real damage caused by vapor cloud explosion suffered before. These are why an expert system for the assessment of vapor cloud explosion has been developed, which is based on theoretical, statistical and experimental data, and it would be helpful for CPI to evaluate the damage-area in case of vapor cloud explosion.

  • PDF

Evaluation of Blast Pressure Generated by an Explosion of Explosive Material (폭발성 물질의 폭발에 따른 폭발압력 평가)

  • Yoon, Yong-Kyun
    • Explosives and Blasting
    • /
    • v.36 no.4
    • /
    • pp.26-34
    • /
    • 2018
  • Explosions of vapor cloud formed due to the leakage from installations with flammable fuels have often occurred in Korea and foreign countries. In this study, TNT equivalency method and Multi-Energy method for vapor cloud explosion blast modelling are described and demonstrated in a case study. As TNT equivalency method is simple and direct, it has been widely used for modelling a vapor cloud explosion blast. But TNT equivalency method found to be difficult to select a proper correlation between the amount of combustion energy produced from the vapor cloud explosion and the equivalent amount of TNT to model its blast effects. Multi-Energy method assumes that the strength of vapor cloud explosion blast depends on the layout of the space where the vapor cloud is spreading. Strictly speaking, the explosive potential of a vapor cloud is dependent upon the density of the obstructed regions. In this study, Flixborough accident are analyzed as a case study to assess the applicability of TNT equivalency method and Multi-Energy method. TNT equivalency method and Multi-Energy method found to be applicable if coefficient of TNT equivalency and coefficient of strength of explosion blast are selected properly.

A Study on the Quantitative Analysis and Estimation for Surround Building caused by Vapor Cloud Explosion(VCE) in LPG Filling Station (LPG충전소에서 증기운폭발이 주변건물에 미치는 영향의 정량적 해석 및 평가에 관한 연구)

  • Leem, Sa-Hwan;Huh, Yong-Jeong
    • Journal of the Korean Society of Safety
    • /
    • v.25 no.1
    • /
    • pp.44-49
    • /
    • 2010
  • This paper is estimation of structure damage caused by Explosion in LPG(Liquefied Petroleum Gas) filling station. As we estimate the influence of damage which occur at gas storage tank in filling station. We can utilize the elementary data of safety distance. In this study, the influence of over-pressure caused by VCE(Vapor Cloud Explosion) in filling station 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 of max 265 meters away and to glass bursting of 1150 meters away was nearly zero in open space explosion.

Development of Design Blast Load Model according to Probabilistic Explosion Risk in Industrial Facilities (플랜트 시설물의 확률론적 폭발 위험도에 따른 설계폭발하중 모델 개발)

  • Seung-Hoon Lee;Bo-Young Choi;Han-Soo Kim
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.37 no.1
    • /
    • pp.1-8
    • /
    • 2024
  • This paper employs stochastic processing techniques to analyze explosion risks in plant facilities based on explosion return periods. Release probability is calculated using data from the Health and Safety Executive (HSE), along with annual leakage frequency per plant provided by DNV. Ignition probability, derived from various researchers' findings, is then considered to calculate the explosion return period based on the release quantity. The explosion risk is assessed by examining the volume, radius, and blast load of the vapor cloud, taking into account the calculated explosion return period. The reference distance for the design blast load model is determined by comparing and analyzing the vapor cloud radius according to the return period, historical vapor cloud explosion cases, and blast-resistant design guidelines. Utilizing the multi-energy method, the blast load range corresponding to the explosion return period is presented. The proposed return period serves as a standard for the design blast load model, established through a comparative analysis of vapor cloud explosion cases and blast-resistant design guidelines. The outcomes of this study contribute to the development of a performance-based blast-resistant design framework for plant facilities.

The Method of Consequence Analysis of the Unconfined Vapor Cloud Explosion Accident by the Continuous Release of Gas-Liquid Flow for the Small and Medium Size Enterprises(SMS) (기-액흐름 연속누출에 의한 개방공간 증기운 폭발사고를 중심으로 중.소규모 사업장을 위한 사고 영향평가 방법)

  • 장서일;이헌창;조지훈;김태옥
    • Journal of the Korean Society of Safety
    • /
    • v.18 no.1
    • /
    • pp.64-70
    • /
    • 2003
  • For the unconfined vapor cloud explosion(UVCE) accident by the continuous release of gas-liquid flow of various saturated liquids in a vessel at ground level, overpressures were estimated by TNT equivalency model with two estimation methods, such as UVCE I model based on a constant release time and UVCEII model based on a real travel time of vapor by dispersion and analyzed with various release conditions. As a simulation result the simple, easy, and correct method of evaluation of consequences of the UVCE accident was proposed by using consequences of UVCE I model and correlation equations for differences of overpressures between UVCE models, so that this evaluation method could be used easily in the small and medium size enterprises without using the dispersion model.

Parameters Affecting the Consequences of the Unconfined Vapor Cloud Explosion Accident by the Release of Heavy Gas (무거운 가스의 누출에 의한 개방공간 증기운 폭발사고에서 사고결과에 미치는 매개변수의 영향)

  • Kim, Tae-Ok;Ham, Byeong-Ho;Cho, Ji-Hoon
    • Journal of the Korea Safety Management & Science
    • /
    • v.9 no.3
    • /
    • pp.21-27
    • /
    • 2007
  • This paper analyses the effect of parameters on the consequences of the unconfined vapor cloud explosion accident (UVCE) by the release of heavy gas (xylene vapor). Simulation results showed that the overpresure was increased with the increase of the release hole diameter and with the decrease of the interested distance and the wind speed. While, the overpresure was not nearly affected by the release height, weather and environmental conditions. From the results of the consequence analysis and analysis of affecting the consequences of UVCE, the emergency plan should be established taking into account these parameters.

Study on the Calculation of the Blast Pressure of Vapor Cloud Explosions by Analyzing Plant Explosion Cases (플랜트 폭발 사례 분석을 통한 증기운 폭발의 폭압 산정법 연구)

  • Lee, Seung-Hoon;Kim, Han-Soo
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.34 no.1
    • /
    • pp.1-8
    • /
    • 2021
  • Vapor cloud explosions show different characteristics from that caused by ordinary TNT explosives and their loading effect is similar to pressure waves. Typical methods used for blast pressure calculations are the TNT-equivalent method and multi-energy method. The TNT-equivalent method is based on shock waves, similar to a detonation phenomenon, and multi-energy method is based on pressure waves, similar to a deflagration phenomenon. This study was conducted to derive an appropriate blast pressure by applying various plant explosion cases. SDOF analysis and nonlinear dynamic analysis were performed to compare the degree of deformation and damage of the selected structural members for the explosion cases. The results indicated that the multi-energy method was more exact than the TNT-equivalent method in predicting the blast pressure of vapor cloud explosions. The blast pressure of vapor cloud explosion in plants can be more accurately calculated by assuming the charge strength of multi-energy method as 7 or 8.

The Consequence Analysis for Unconfined Vapor Cloud Explosion Accident by the Continuous Release of Gas-Liquid Flow (기-액흐름 연속누출에 의한 개방공간 증기운 폭발사고의 영향평가)

  • 장서일;이헌창;김태옥
    • Journal of the Korea Safety Management & Science
    • /
    • v.4 no.3
    • /
    • pp.35-43
    • /
    • 2002
  • For the unconfined vapor cloud explosion accident by the continuous release of gas-liquid flow of various saturated liquids in a vessel at ground level, overpressures were estimated and analyzed with various release conditions and materials by TNT equivalency model with vapor dispersion. We found that at same release conditions, overpressure showed n-heptane > xylene > n-hexane > toluene > n-heptane > benzene, respectively and that overpressure was increased with increasing the hole diameter and the storage pressure, but it was increased with decreasing the wind speed, the interested distance, and the vessel thickness.

Construction of Expert System for Hazard Assessment of Unconfined Vapor Cloud Explosion (증기운 폭발의 위험성 평가를 위한 전문가 시스템의 구축)

  • 함병호;손민일;김태옥;조지훈;이영순
    • Journal of the Korean Society of Safety
    • /
    • v.10 no.2
    • /
    • pp.97-104
    • /
    • 1995
  • To evaluate readily the effect of unconfined vapor cloud explosion(UVCE) having high possibility of accident and risk in chemical industries, the expert system of UVCE was developed and its applicability on a real accident was analyzed. We found that the hazard of UVCE could be well evaluated from the TNT equivalency model and the empirical loss data produced by overpressure for chemical facilities. By using the developed expert system, the size of vapor cloud, the quantity of vaporization, the released energy, the overpressure range from explosion point, and the impact damage of each installation could be estimated respectively. Also, probable maximum loss and catastrophic loss potential for real accident( cyclohexane release in Flixborough Nypro company) were estimated and compared with damages of the accident. As a result, the developed expert system could be well applicable to real accident.

  • PDF

A Study on Safety Assessment of Hydrogen Station (수소충전소의 안전성 평가 연구)

  • PYO, DON-YOUNG;KIM, YANG-HWA;LIM, OCK-TAECK
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.30 no.6
    • /
    • pp.499-504
    • /
    • 2019
  • Due to the rapid spread and low minimum ignition energy of hydrogen, rupture is highly likely to cause fire, explosion and major accidents. The self-ignition of high-pressure hydrogen is highly likely to ignite immediately when it leaks from an open space, resulting in jet fire. Results of the diffusion and leakage simulation show that jet effect occurs from the leakage source to a certain distance. And at the end of location, the vapor cloud explosion can be occurred due to the formation of hydrogen vapor clouds by built-up. In the result, it is important that depending on the time of ignition, a jet fire or a vapor cloud explosion may occur. Therefore, it is necessary to take into account jet effect by location of leakage source and establish a damage minimizing plan for the possible jet fire or vapor cloud explosion. And it is required to any kind of measurements such as an interlock system to prevent hydrogen leakage or minimize the amount of leakage when detecting leakage of gas.