关于检测煤炭自燃的潜在火灾危害的初步勘探,采用声波波应用
Shuai-Jing Ren1, Yan-Ni Zhang2, Ze-Yang Song2
1School of Safety Science and Engineering, Xi'an University of Science and Technology, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China; School of Energy Engineering, Xi'an University of Science and Technology, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China.
The Science of the total environment
|July 13, 2023
概括
松散煤中的声波衰减主要受到空隙分布的影响,空隙分布与颗粒大小有关. 这项研究支持使用声学方法来检测煤炭中的高温,以防止自燃.
科学领域:
- 地质物理学 地质物理学
- 材料科学 材料科学 材料科学
- 燃烧科学 燃烧科学
背景情况:
- 煤炭自燃导致资源浪费和环境污染.
- 早期检测煤炭中高温区域对于预防至关重要.
- 声学温度计为温度测量提供非接触式,高干扰性耐阻.
研究的目的:
- 为了研究宽松煤中的声波衰减特征.
- 为了确定煤炭特性 (颗粒大小,温度,变态程度) 和声衰减之间的关系.
- 为声学温度计在煤炭中检测高温区提供理论支持.
主要方法:
- 计算机断层扫描被用来分析四种煤类型的空隙分布.
- 一个自行设计的声衰减测试装置在不同的温度和颗粒大小下测量了衰减系数.
- 在松散煤中分析声波传播和衰减机制.
主要成果:
- 松散的煤炭空隙分布与颗粒大小密切相关;较小的颗粒产生更均的空隙,而较大的颗粒产生更大的空隙.
- 对于所有煤样品,声衰减系数随频率的增加而增加.
- 煤颗粒大小分布对声衰减有很大的影响,比温度或变态程度更大.
- 峰值声衰减发生在与粒子大小相关的特定频率 (400,700,1100,1600 Hz) 上,这表明空隙分布是影响声波传播的主要因素.
结论:
- 由颗粒大小决定的空隙分布是影响松散煤中的声波传播和衰减的主要因素.
- 声波减弱是由于松散煤的联合吸收和散射而产生的.
- 这些发现为使用声波检测来识别容易发生自燃的煤炭中高温点提供了理论基础.
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