A three-dimensional simulation of the effects of obstacle blockage ratio on the explosion wave in a tunnel

Zhao, Xiaolong; Chen, Changkun; Shi, Congling; Chen, Jie; Chen, Qingzhong

doi:10.1007/s10973-020-09777-7

Cited by 10 publications

(3 citation statements)

References 32 publications

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“…Some scholars have researched blockage effects and related numerical algorithms. Zhao et al [6], using LS-Dyna software, established a three-dimensional physical model of a tunnel, characterizing explosion waveforms, maximum explosion overpressure, and the arrival time of peak pressure near obstacles with different blockage ratios. Li [7] focused on the interaction between explosion waves and obstacles using commercial CFD software, comparing and analyzing the differences in shock wave reflection and diffraction under obstacles of different geometric sizes.…”

Section: Introductionmentioning

confidence: 99%

Research on the blockage effect in a shock tube

Shao

2024

TNS

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The shock tube is a crucial experimental apparatus in the field of explosive impact. Limited research has been conducted on the visualization of the internal flow field in shock tubes under blockage conditions, and there is a lack of comprehensive understanding of the mechanisms behind blockage effects. This paper presents experimental and numerical investigations into the propagation of shock waves inside a shock tube and their interaction with obstructive elements. Blockage effect experiments were conducted on a shock tube test platform, where pressure data were obtained through a pressure monitoring system. Additionally, schlieren imaging technology was employed to visualize the evolution of shock wave fronts. A two-dimensional numerical model of the shock tube was established using Fluent software, and the computed results exhibited excellent agreement with the experimental data, confirming the accuracy of the numerical model. The mechanism of the blockage effect was revealed through analysis of pressure-time curves and images depicting the evolution of shock wave fronts. Furthermore, adjustments to parameters on the validated numerical model allowed for analysis and comparison of different blockage ratios. The results indicate that the disturbance to the flow field caused by the blockage effect is primarily due to the reflection of shock waves between the front surface of the obstructive element and the shock tube wall. This reflection leads to differences in pressure curves compared to free-field conditions, and such differences increase with higher blockage ratios.

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Section: Introductionmentioning

confidence: 99%

Research on the blockage effect in a shock tube

Shao

2024

TNS

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“…Over the recent years, the explosive characteristics of combustible gas with barriers have been extensively studied experimentally. 7 , 8 These studies focused on the shape, 9 − 15 blockage ratio, 16 − 19 location, 20 − 23 number, 24 − 26 spacing, 27 , 28 and fuel concentration. 29 − 33 Further, experiments have been conducted to obtain the explosive pressure parameters and flame transmission characteristics.…”

Section: Introductionmentioning

confidence: 99%

“…Over the recent years, the explosive characteristics of combustible gas with barriers have been extensively studied experimentally. , These studies focused on the shape, − blockage ratio, − location, − number, − spacing, , and fuel concentration. − Further, experiments have been conducted to obtain the explosive pressure parameters and flame transmission characteristics. The results indicated that the number of barriers can increase the flame propagation speed and peak pressure, but the peak pressure is not entirely determined by the number of barriers.…”

Section: Introductionmentioning

confidence: 99%

Effect of a Perforated Polyethylene Material on Propane–Air Explosion in a Confined Space

Qiao

Long³

2022

ACS Omega

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In this study, the effect of polyethylene barriers with different blockage ratios on the explosion behavior of a propane–air premixed gas in a confined space is investigated. The maximum explosion pressure (P max), the deflagration index (K G), and the flame propagation process of the propane–air premixed gas with different barrier thicknesses are examined by using a horizontal closed tube with a length of 0.5 m and a diameter of 0.1 m and a high-speed camera. The atmospheric pressure and temperature of the premixed gas were 101.3 kPa and 18 °C, respectively. Based on the Canny operator, the position of the flame front at different times and the shape of the barriers before and after the explosion are determined, and the propagation speed of the premixed flame and the deformation rate of the barriers are obtained. The results indicate that the barriers change the flow field structure of the unburned gas and increase the folding degree of the flame front. With the increase in the blockage ratio, the explosion of a premixed system becomes more rapid and violent. Under the action of Rayleigh–Taylor instability, the variation in the flame propagation speed induces a change in the tube pressure. In addition, the deformation of a barrier causes a change in the maximum explosion pressure. The greater the deformation ratio of the barrier after the explosion, the larger the maximum explosion pressure.

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