Article
Thermodynamics
Xing Yu, Yue Wu, Yanqiu Zhao, Changjian Wang
Summary: In this work, the characteristics of cryogenic hydrogen fires were investigated experimentally, including flame size, radiative power, and flame temperature. The results showed that flame size was influenced by nozzle diameter, stagnation pressure, and temperature. A correlation model was proposed for predicting flame size at different temperatures.
COMBUSTION AND FLAME
(2022)
Article
Chemistry, Physical
Dinggen Li, Renlang Wang, Gang Yang, Jianlong Wan
Summary: This study investigates the effect of hydrogen addition on the structure and stabilization of micro-jet methane diffusion flame through numerical simulation. The results show that hydrogen addition can make the flame more circular, suppress the increase in flame height with inlet velocity, and improve flame stabilization. However, excessive hydrogen addition may have detrimental effects on flame stabilization.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Energy & Fuels
Yuke Gao, Zhengkang Lu, Yang Hua, Yongqiang Liu, Changfa Tao, Wei Gao
Summary: This study investigates the radiation fraction of a turbulent diffusion jet flame using propane and hydrogen as fuel gases. It is found that the dilution effect of hydrogen on propane is limited, and the radiation fraction changes slightly with the increase in hydrogen flow rate.
Article
Thermodynamics
Junjun Guo, Lingqi Shen, Xiaoyi He, Zhaohui Liu, Hong G. Im
Summary: The study evaluates the weighted sum of gray gases (WSGG) models for turbulent jet diffusion flame simulations, showing that the model based on mixture modeling provides good prediction accuracy with lower computational cost. The combination of mixture modeling with non-gray soot radiative property model offers the best accuracy for gas-soot mixture.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
K. Utria, S. Labor, M. Kuhni, D. Escudie, C. Galizzi
Summary: This study experimentally investigated H-2/O-2 downward coflow multi-fuel-jet inverse diffusion flames and analyzed them through visualization and chemiluminescence diagnostics. Three types of flame structure were identified, and two reaction zones were determined. The characteristics of the diffusion zones are controlled by the oxygen momentum, while the central reaction zone depends on the strength of the momentum ratio and the oxygen jet momentum.
EXPERIMENTAL THERMAL AND FLUID SCIENCE
(2022)
Article
Chemistry, Physical
Ho Lung Yip, Ales Srna, Guanxiong Zhai, Armin Wehrfritz, Sanghoon Kook, Evatt R. Hawkes, Qing Nian Chan
Summary: This study investigates the mechanisms governing H2 jet flame evolution and stabilization by controlling the jet ignition location using a laser-induced plasma. The experiments examine the flame evolution in a constant-volume combustion chamber under various ambient O2 concentrations and temperatures. The results show that a localized flame kernel forms at the laser-induced plasma and spreads to engulf the entire upstream and downstream jet volume. The flame lift-off is sensitive to ambient O2 and temperature changes, and the edge-flame deflagration into stratified premixed fuel-ambient reactant streams explains the lift-off response.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Aerospace
Chaoyang Liu, Ning Wang, Kai Yang, Dongpeng Jia, Yu Pan
Summary: This study focuses on the stabilization mechanism of a supersonic lifted jet flame in heated coflows, highlighting the competition between autoignition and the propagation of active kernels at the flame base. Using highly-resolved large eddy simulation, it is found that the characteristics of the lifted hydrogen jet combustion gradually vary along the axial direction, with the evolution of turbulent structures and flameholding mechanism being crucial.
Article
Thermodynamics
Carmen Jimenez, Vadim N. Kurdyumov
Summary: This article presents a numerical investigation on the combustion process occurring after fuel and oxidizer are separately injected into a planar channel from an end-wall porous plug. The results show that symmetrical and non-symmetrical configurations of edge flames are possible for the same set of parameters, and that there can be at least seven different steady-state solutions. These findings are critical for flames with low fuel Lewis number, such as hydrogen flames, and emphasize the importance of considering the possibility of non-symmetrical flame configurations in the design and operation of combustion devices based on diffusion flames.
COMBUSTION AND FLAME
(2023)
Article
Engineering, Environmental
Chunxiang Zhao, Xing Li, Xiaohan Wang, Min Li, Huahua Xiao
Summary: This paper experimentally studied the characteristics of H-2/CH4 jet flames at varied heat release rates (HRRs) with H-2 volume fraction (fv) ranging from 0% to 90%. The results showed that the flame height is affected by the increase in mixture molecular diffusivity, radicals pool, air entrainment, flame temperature, and jet velocity of fuel flow. A flame height model for H-2/CH4 flames was obtained through comparisons of different correlations.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2023)
Article
Energy & Fuels
Tao Chen, Suyuan Yu, Yu Cheng Liu
Summary: The study investigates the effects of Soret diffusion on hydrogen-air edge flame propagation and diffusion-chemistry interaction through simulation. It demonstrates that Soret diffusion significantly influences the relationships between flame displacement speed and flame curvature, stretch rate, and scalar dissipation rate. Additionally, Soret diffusion weakens the chemical reaction component in edge flame propagation and affects the diffusion of hydrogen and hydrogen-2 in opposite ways.
Article
Chemistry, Physical
H. A. J. Froeling, M. T. Droge, G. F. Nane, A. J. M. Van Wijk
Summary: This paper focuses on the risk analysis of hydrogen transmission in existing pipelines, comparing the individual risk associated with hydrogen jet fires with natural gas. The analysis shows that hydrogen jet fires yield lower lethality levels and decrease faster with distance than natural gas jet fires, leading to significant lower individual risk in large pipelines. However, ignition effects dominate the individual risk for decreasing pipeline diameters, causing increased individual risk in the vicinity of the pipeline compared to natural gas.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Engineering, Multidisciplinary
Islam M. Mesallam, Ahmed A. A. Attia, Khairy H. El-Nagar, Ismail M. M. Elsemary
Summary: In this study, a diffusion jet flame consisting of a newly developed flame holder with three coaxial pipes to transfer air and fuel to the combustion zone, is experimentally investigated to simulate the ramjet effect. The results showed that the secondary air exit location had an effect on the flame temperature distribution, flame shape, flame length, and flame width. The optimum position of the secondary air pipe was found above the datum line at Z5 = 7.5 mm, where the flame temperature and length are considered relatively high compared to other secondary air pipe positions.
ALEXANDRIA ENGINEERING JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Ruibang Sun, Juncai Wang, Xing Yang, Peng Chen
Summary: This study conducted experiments to investigate the characteristics of transformer oil jet fire, deriving functional relationships between flame height and mass flow, as well as flame temperature and axial height. A prediction model for radiant heat flux of transformer oil jet fire was established, which is significant for improving fire protection design in substations and enhancing fire management and control capabilities.
Article
Chemistry, Applied
Jiabao Yang, Yan Gong, Juntao Wei, Qinghua Guo, Fuchen Wang, Guangsuo Yu
Summary: This paper explores the feasibility of evaluating the molar equivalence ratio of oxygen to fuel in fuel-rich conditions using radical chemiluminescence diagnosis. The sensitivity of luminescence intensity to the change of oxygen/fuel ratio was quantitatively studied, and the two-dimensional distributions of intensity ratios were analyzed to reconstruct local oxygen/fuel ratios. The results show that OH* chemiluminescence is more sensitive to changes in oxygen/fuel ratio compared to CH* and CO2*.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Thermodynamics
Cheng Tung Chong, Bo Tian, Jo-Han Ng, Luming Fan, Manh-Vu Tran, Cen Zhang, Simone Hochgreb
Summary: This study investigates the generation of soot from biodiesel combustion and its blend with fossil diesel under different flame conditions. The results show that biodiesels with higher saturation produce less soot. The effects of chemical compositions on soot generation are analyzed using design of experiments methodology. The study suggests an optimal synthetic biodiesel mixture composition for the lowest soot generation.
COMBUSTION AND FLAME
(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)
