Flame and temperature wave propagation characteristic of methane‐air mixture in mine tunnels

In this paper, vibration and wave propagation characteristics of auxetic metamaterial of the star-shaped structure system are studied. The plane wave expansion method is adopted to investigate and calculate the band structures of the auxetic star-shaped structure system. Besides, the frequency ranges of the complete bandgaps are also obtained and discussed. Then, the COMSOL® finite element software is utilized to solve wave propagation characteristics within the periodic auxetic star-shaped honeycomb structures. After that, the auxetic star-shaped structure devices made by 3D printed machine are used to measure the experimental results and also compared with numerical results. It can be seen that good agreements can be found in the discussions.

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An FMM-FFT accelerated integral equation solver for characterizing electromagnetic wave propagation in mine tunnels and galleries loaded with conductors

2014 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium) ◽

10.1109/usnc-ursi.2014.6955447 ◽

2014 ◽

Cited By ~ 1

Author(s):

Abdulkadir C. Yucel ◽

Yang Liu ◽

Hakan Bagci ◽

Eric Michielssen

Keyword(s):

Integral Equation ◽

Wave Propagation ◽

Electromagnetic Wave ◽

Electromagnetic Wave Propagation ◽

Mine Tunnels

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Theoretical and Experimental Investigation on Laser-Generated Guided Wave Propagation Characteristic of an Overlying Plate/Substrate

Acta Acustica united with Acustica ◽

10.3813/aaa.918647 ◽

2013 ◽

Vol 99 (5) ◽

pp. 687-693

Author(s):

Hao Wang ◽

Qingbang Han ◽

Menglu Qian

Keyword(s):

Experimental Investigation ◽

Wave Propagation ◽

Propagation Characteristic ◽

Guided Wave ◽

Guided Wave Propagation

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Impact of Rough Wall Surface on Electromagnetic Wave Propagation Characteristics in Mine Tunnels

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.301-303.1417 ◽

2011 ◽

Vol 301-303 ◽

pp. 1417-1421

Author(s):

Shan Hua Yao ◽

Xian Liang Wu

Keyword(s):

Wave Propagation ◽

Electromagnetic Wave ◽

Coal Mine ◽

Electromagnetic Waves ◽

Electromagnetic Wave Propagation ◽

Rough Wall ◽

Wall Surface ◽

Propagation Characteristics ◽

Waves Propagation ◽

Mine Tunnels

In this paper ,the mine tunnels is regard as wave-guide which contains kinds of un-beneficial medium, we have study the formulas of electromagnetic waves propagation attenuation and roughness attenuation, the relations between propagation attenuation and roughness and frequency were simulated. The results show that the influence of propagation attenuation in lower frequency is more obvious, and roughness attenuation is increased rapidly as roughness of coal mine tunnels increasing. But tilted attenuation is stronger than roughness attenuation as propagation frequency increasing.

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Application of Information Entropy in the Cement Grouting Test Using Impact Acoustics

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.584-586.1217 ◽

2014 ◽

Vol 584-586 ◽

pp. 1217-1223

Author(s):

Jin Cheng ◽

Qing Bang Han ◽

Hong Hui Fan

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Wave Propagation ◽

Information Entropy ◽

Sound Field ◽

Propagation Characteristic ◽

Defect Size ◽

Impact Echo ◽

Complex Wave ◽

Lower Entropy

The unqualified corrugated pipe grouting quality in bridges will lead to serious safety accidents. The sound field propagation in corrugated pipe structure was simulated and analyzed using finite element method, a much complex wave propagation characteristic is demonstrated, and the scattering signals caused by grouting defect are hardly distinguished. The collected impact-echo signals were processed by signal processing of information entropy technology. It is found the defect size is directly related to the information entropy. Several simulated models are constructed and measured, and the bigger size defect is, the lower entropy value is.

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