Experimental study on explosion characteristics of premixed syngas/air mixture with different ignition positions and opening ratios

Yao, Zhifeng; Deng, Haoxin; Zhao, Weilong; Wen, Xiaoping; Dong, Jianfei; Wang, Fahui; Chen, Guoyan; Guo, Zhang

doi:10.1016/j.fuel.2020.118426

Cited by 41 publications

(11 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The inflation was then completed, and the mixtures within the channel were allowed to settle for 30 s before ignition. 49 − 51 Later, ignition started, and the duration of the spark was about 1 ms, while the pressure and picture acquisition systems started to collect data. The shooting speed of the high-speed camera was 3000 f/s.…”

Section: Methodsmentioning

confidence: 99%

Experimental Studies on the Explosion Behaviors of Premixed Hydrogen–Air Mixtures in a Narrow Channel

Zhang

Wen

et al. 2022

ACS Omega

Self Cite

View full text Add to dashboard Cite

Premixed hydrogen–air explosion experiments were carried out in a 1000 mm × 50 mm × 10 mm half-open narrow channel, concerning with the influences of equivalence ratio and ignition position on explosion behaviors. Experimental phenomena were different from explosion in large space. The results indicated that when ignited at the closed end of the channel, three overpressure peaks appeared, caused by the rupture of the film, Helmholtz Oscillation, and the flame-acoustic interaction, respectively. As the equivalence ratio of the hydrogen–air mixtures varied from 0.6 to 1.6, the peak overpressure first increased and then decreased. The maximum peak overpressure occurred at ϕ = 1.2. The hydrogen flame would develop into the plane tulip structure without the influence of the end wall. With the ignition position moved to the open end, overpressure wave and flame oscillated significantly. Compared with other ignition positions, the minimum value of P max was obtained at IP 950 . Based on the explosion behaviors in the narrow channel, it was concluded that the closer the ignition was to the open end, the easier the oscillation was to be formed, the smaller the explosion hazard was.

show abstract

Section: Methodsmentioning

confidence: 99%

Experimental Studies on the Explosion Behaviors of Premixed Hydrogen–Air Mixtures in a Narrow Channel

Zhang

Wen

et al. 2022

ACS Omega

Self Cite

View full text Add to dashboard Cite

show abstract

“… 12 Yao et al concluded that when the ignition position was the same, the overpressure growth rate and the maximum overpressure decreased as the opening rate increased. 13 Pan et al studied the explosion experiments of rectangular containers with circular and square vents and found that the amplitude of flame tip propagation oscillations under circular vents was greater than that of the square ones. 14 Qi et al studied the effect of three kinds of vents of 25, 50, and 100 cm 2 on the gasoline vapor–air-premixed explosion characteristics and found that the external pressure of 25 and 50 cm 2 vents increased more significantly than that of the 100 cm 2 vent.…”

Section: Introductionmentioning

confidence: 99%

Study on the Influence of Vent Shape and Blockage Ratio on the Premixed Gas Explosion in the Chamber with a Small Aspect Ratio

et al. 2022

View full text Add to dashboard Cite

Given the current situation of deflagration caused by gas leakage for domestic use and the study of the single shape of the vent, the differential change law of vent parameters on the small aspect ratio of the chamber explosion flame evolution and explosion overpressure and other effects were experimentally investigated. Based on the theory of geometric similarity, the experimental platform of a small length–diameter ratio explosion chamber was designed and built, and the premixed gas explosion experiment was carried out by changing the shape (square and rectangle) and blockage ratio (0.1, 0.3, 0.5, 0.7, and 0.9). The explosion flame structure, flame front position, flame propagation speed, explosion pressure waveform, overpressure peak value, and so on were tested and analyzed. The results showed that the blockage ratio had the most significant effect on flame propagation and explosion flame evolution. With the increase of blockage ratio, the stretching degree of the flame became more and more obvious, the flame front became sharper and sharper, and the sharp flame changed from the lower part to the upper part. The position of the flame front increased rapidly, and the steepness and peak value of explosion overpressure became larger. The oscillation of the flame propagation velocity was more violent after the turn, and the speed of propagation to the outside of the chamber gradually accelerated. In the same blockage ratio, there was a difference in the time point at which the flame propagation velocity turned under the rectangular and square shape of the vent. In blockage ratios of 0.1, 0.3, 0.5, and 0.9, the peak overpressure reduction under the shape of the blast square relative to the rectangle was 41.3, 47.9, 1.03, and 27.6%. This indicated that the explosion relief effect of the square was better than that of a rectangle. The research results can provide a reference and basis for the reasonable deployment of explosion venting and explosion decompression work.

show abstract

“…Their experimental results show that the increase in the pressure amplitude is closely related to the change in the opening ratio and the hydrogen volume fraction. Wen et al 7 also analyzed the opening ratio and the ignition position of syngas in a rectangular duct. Sun 8 and Singh et al 9 conducted experimental work to measure the laminar flame speed and explosion overpressure of premixed syngas/air mixtures in the spherical combustion.…”

Section: Introductionmentioning

confidence: 99%

Flame Propagation Characteristics of Syngas-Air in the Hele-Shaw Duct with Different Equivalence Ratios and Ignition Positions

et al. 2022

Self Cite

View full text Add to dashboard Cite

In this paper, the effects of different ignition positions and equivalence ratios on the explosion characteristics of syngas in a half-open Hele-Shaw duct were investigated. The ignition points are set at distances of 0 and 500 mm from the closed end. Moreover, the research range of equivalence ratio is 0.8–1.2. The experimental results indicate that different ignition positions and equivalence ratios influence the flame front structure and the dynamic characteristics of flame propagation. When the ignition position is at the closed end, the flame front undergoes several typical propagation stages before eventually reaching the open end of the duct. The time required by the flame to reach the open end decreases as the equivalence ratio increases. Meanwhile, when the ignition is in the middle of the duct, the flame simultaneously spreads to the open and closed ends. The time required to reach both sides decreases with the increase in the equivalence ratio. The flame front structure and pressure are primarily affected by the ignition position and the equivalence ratio. At the same ignition position, flame propagation velocity and maximum overpressure increase with the equivalence ratio. The pressure oscillation becomes more intense when the ignition position is close to the open end. At IP 500 , when the equivalence ratio is 0.8, multiple finger-shaped flame fronts emerge, accompanied by high-frequency flame oscillations. This study can provide guidance for the study of the flame propagation characteristics of syngas in millimeter-scale burners.

show abstract

Experimental study on explosion characteristics of premixed syngas/air mixture with different ignition positions and opening ratios

Cited by 41 publications

References 49 publications

Experimental Studies on the Explosion Behaviors of Premixed Hydrogen–Air Mixtures in a Narrow Channel

Experimental Studies on the Explosion Behaviors of Premixed Hydrogen–Air Mixtures in a Narrow Channel

Study on the Influence of Vent Shape and Blockage Ratio on the Premixed Gas Explosion in the Chamber with a Small Aspect Ratio

Flame Propagation Characteristics of Syngas-Air in the Hele-Shaw Duct with Different Equivalence Ratios and Ignition Positions

Contact Info

Product

Resources

About