Article
Engineering, Chemical
Darren R. Malik, J. Kelly Thomas, Oscar A. Rodriguez, Bradley J. Horn, Jihui Geng
Summary: This paper discusses potential mitigation options for reducing the severity of large vapor cloud explosions, such as multiple ignition sources, suppressants, and controlling flame travel distance. A test program was conducted using near-stoichiometric ethylene-air mixtures to determine the free vent distance needed to prevent detonation.
PROCESS SAFETY PROGRESS
(2021)
Article
Engineering, Chemical
Yongzhong Bai, Baoquan Xin, Jianliang Yu, Wenyi Dang, Xingqing Yan, Anfeng Yu
Summary: A triangular pyramid explosion risk model was established in this study, combining overpressure, duration, and frequency of the explosion scene. Blast-resistant and defense loads of buildings were quantitatively determined based on this model, emphasizing the explosion risk value. Key variables affecting the explosive load included the explosion scene and its frequency, the volume of the obstructed region, and the distance of the explosion source.
JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
(2021)
Article
Engineering, Chemical
Darren R. Malik, W. B. Lowry, E. Vivanco, J. K. Thomas
Summary: Hydrogen is a crucial energy carrier in modern society and there is a global push for lower carbon energy vectors, including pure hydrogen. Accurately modeling the hazards associated with hydrogen production, distribution, and consumption is crucial for the safe expansion of these networks.
PROCESS SAFETY PROGRESS
(2023)
Article
Thermodynamics
Vadim N. Gamezo, Christian L. Bachman, Elaine S. Oran
Summary: The study reveals that blockage ratio and distance between obstacles play crucial roles in the evolution of flames, with increased blockage ratio and decreased distance promoting flame acceleration. Additionally, certain configurations can prevent detonation development. Furthermore, the distance at which the shock-flame complex forms serves as an important measure of explosive potential.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Engineering, Marine
Fang Han, Xue Hongxiang, Tang Wenyong
Summary: Gas explosions can cause catastrophic damage to structures and humans, but the use of blast walls can effectively prevent this damage. This study analyzes the effect of gas cloud characteristics on explosion pressure distribution and the impact of non-uniform loads on structural responses. The results show that explosion loads have strong spatial inhomogeneity in scenarios with large cloud size or long combustion distance. Therefore, both global and local explosion pressures should be considered in the design of blast walls, and overpressure-probability exceedance curves for non-uniform explosion pressures are recommended.
Article
Energy & Fuels
Xianzhao Song, Jing Zhang, Quan Liu, Qiming Xu, Jiu Chen, Dan Zhang, Lifeng Xie, Bin Li
Summary: Experiments were conducted to study the effects of hydrogen concentrations and vent areas on vented hydrogen-air explosion. The results showed that the pressure oscillation frequency increased with hydrogen concentration and the Helmholtz oscillation disappeared with the increase of K-v. Higher dynamic loading was experienced at positions farther away from the vent cover. In addition, the external field had lower hydrogen concentration, and the external flame velocity was greater for rich fuel. Deflagration to detonation was easier to achieve for concentrations near 50 vol% and lower K-v.
Article
Energy & Fuels
Xianzhao Song, Jing Zhang, Quan Liu, Qiming Xu, Jiu Chen, Dan Zhang, Lifeng Xie, Bin Li
Summary: The study showed that hydrogen concentrations and vent areas have significant effects on vented hydrogen-air explosions. Increasing hydrogen concentration led to higher pressure oscillation frequency and gradual disappearance of Helmholtz oscillation. Higher hydrogen concentrations resulted in higher dynamic loading, and there is a relationship between external field hydrogen concentration and Kv, affecting explosion patterns and flame velocities.
Article
Engineering, Chemical
Shuya Hou, Yi Liu, Zhi Wang, Mingju Jing, Yingnan Zhang, Bin Zhang
Summary: This study investigated a large vapor cloud explosion resulting from an LPG transportation accident in Wenling City, China. The analysis showed that DDT occurred in the accident and provided scientific recommendations for preventing similar incidents.
JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
(2022)
Article
Thermodynamics
Xiaoyi Lu, Carolyn R. Kaplan, Elaine S. Oran
Summary: This paper presents a numerical study of flame acceleration and deflagration-to-detonation transition (DDT) of hydrogen-air mixtures in a channel with obstacles, where the mixture composition has a spatial gradient perpendicular to the wave propagation direction. The simulation results show that the ease with which an inhomogeneous mixture can detonate is bounded by the detonation limits of the most and least detonable homogeneous mixture.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Chemistry, Physical
Min Li, Huahua Xiao
Summary: This study investigated flame acceleration and deflagration-to-detonation transition (DDT) in a channel with staggered cylindrical obstacles and a stoichiometric hydrogen-air mixture. The results showed that the mechanisms of flame acceleration and transition to detonation were consistent, and were affected by the spacing of the obstacles. The flame propagation speed and DDT run-up distance and time were found to be highly dependent on the obstacle spacing.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Yangyang Cui, Cheng Wang, Dongping Chen, Chengeng Qian, Boyang Qiao
Summary: This study experimentally measured the scaling-effect of explosion characteristics in mixture explosions and found that the explosion overpressure of mixtures increases rapidly with hydrogen mole fractions, exhibiting a clear dependence on tube size in large tubes.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Kun Zhao, Zhirong Wang, Chi Ma, Xingyan Cao, Pinkun Guo, Wenjie Guo, Yawei Lu
Summary: The study on chained explosions shows that vapor diameter affects the overpressure, while ignition position plays a significant role in the development trajectory.
Article
Thermodynamics
Shervin Hashemi Mehr, Gaby Ciccarelli
Summary: Self-luminous high-speed photography was used to study flame acceleration and deflagration-to-detonation transition (DDT) in a clear polycarbonate round tube equipped with orifice plates. The study found a linear relationship between flame acceleration and one-half of the Chapman-Jouguet detonation velocity (VCJ) for the most reactive mixture conditions, but this relationship deviated with decreasing initial pressure, especially at the DDT limit. Therefore, a correlation for the DDT run-up distance based on the concepts of flame acceleration and induction phase was proposed.
COMBUSTION AND FLAME
(2023)
Article
Engineering, Environmental
Saumitra Mishra, Kirti Bhushan Mishra
Summary: This study aimed to predict the explosion characteristics of LNG-air clouds using advanced 3D CFD techniques, validating the results against similar experiments. The simulations revealed that LNG-air mixture has a higher flame speed and explosion overpressure compared to LPG-air mixture, with a high likelihood of occurrence of DDT. The detailed study on DDT occurrence in an LNG plant is beneficial for setting safety measures and mitigation strategies.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2021)
Article
Chemistry, Physical
Xuechen Xi, Cheng Tian, Kuanliang Wang
Summary: This study investigates the application of methane in hypersonic propulsion and finds that initiating oblique detonation waves (ODWs) in methane-air mixtures is challenging, resulting in long initiation length. The addition of hydrogen to methane is proposed to decrease the initiation length and expand the application range. A theoretical model for the initiation length of fuel blends is proposed, and the advantages of methane fuel in ODW-based propulsion are discussed based on the effects of hydrogen addition on total pressure.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Engineering, Chemical
Chao Chen, Hang Chen, Li Mo, Shenbin Xiao, Changjun Li, Ming Yang, Genserik Reniers
Summary: Fire-induced domino effect is a major threat to hazardous material storage tanks. Previous research neglected the impact of wind load on the thermal buckling behavior of tanks exposed to fire. This paper conducts a numerical simulation to analyze the synergistic effects of fire and wind loads on the thermal post-buckling behavior of storage tanks, considering wind parameters and heat radiation parameters.
JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
(2024)
Article
Engineering, Chemical
Zhang Chu, Liu Lili, Li Wei, Li Beibei, Liu Mingxing
Summary: This study predicts the fatigue life of blasting discs using a combined simulation method and measures the deformation of conventional slotted blasting discs subjected to repeated loading using a high-precision laser scanning method. A relationship model is established between deformation, loading pressure, cycle number, and change in blasting pressure. The results show that the deformation varies linearly with the cycle number and follows a power function relationship with the change in blasting pressure. The deformation can be used to accurately predict the fatigue life of blasting discs.
JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
(2024)
Article
Engineering, Chemical
Shin-Mei Ouyang, Jia-Chi Ye, Wei-Chun Chen, Yu-Jen Chen, Chin-Feng Chen
Summary: This study employed the Taguchi method and analysis of variance to investigate the factors that influence the deterioration of pyrotechnics when stored under different humidity and temperature conditions. Various experimental methods were used to study the microstructure, heat flow, and safety of the pyrotechnics. The results showed that humidity had a significant impact on the pyrotechnics, and controlling humidity could reduce the hazards associated with storing pyrotechnics.
JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
(2024)
Article
Engineering, Chemical
Bei Li, Huiqiang Liu, Heng Gao, Chi-Min Shu, Mingshu Bi
Summary: The moisture content sprayed into the dust layer in industrial sites is a main factor affecting reignition. The study found that moisture has a certain influence on the thermophysical properties of the dust layer, playing an important role in heat transfer and heat absorption processes. The results showed that as the moisture content increased, the thermal conductivity and heat sink density of the sample increased, indicating the need to have a heat sink density higher than the heat increase value to suppress ignition.
JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
(2024)
Article
Engineering, Chemical
Yue Jing, Yong Pan, Fan Yang, Dan Wei, Wenhe Wang
Summary: A comprehensive risk assessment method for the esterification process was proposed in this study. It established a comprehensive evaluation index system and utilized improved Dempster-Shafer evidence theory and cloud model for assessment. The method was validated through case studies and showed consistency with established indexes.
JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
(2024)