【摘要】 利用煤岩低频电磁辐射实验系统,采集型煤试样单轴压缩加载过程中的低频电磁辐射信号。基于希尔伯特-黄变换(HHT)的降噪原理去除高频噪声,得到有效低频电磁信号成分,并将有效低频电磁辐射信号幅值和压力进行关联分析,得出低频电磁辐射信号的能量变化规律和频率分布范围。结果表明:在型煤压密阶段,低频电磁信号幅值和能量较大;在煤体线弹性阶段,会阵发性的产生低频电磁信号,但是其能量较弱;在型煤破裂阶段,低频电磁信号幅值和能量急剧增强。低频电磁辐射信号的频段范围为0~18 Hz,型煤破裂过程电磁信号具有较明显的低频特性,且幅值和能量的变化能很好地反映型煤的破裂状况。更多还原

【Abstract】 Using low-frequency electromagnetic radiation experiments of coal and rock,the paper received low-frequency electromagnetic radiation signal through Briquette experiments under uniaxial loading experiments. Effectively low frequency electromagnetic signals are obtained through removing high-frequency noise based on HHT reduction principle,the paper analyzed amplitude and pressure relationship of effective low-frequency electromagnetic radiation signal and drew the energy variation laws of low-frequency electromagnetic signal and frequency range. Analysis results showed that amplitude and energy of low frequency electromagnetic signal became larger in the Briquette compaction stage; in the coal linear elastic stage,low-frequency electromagnetic signals were paroxysmal generated,however,its energy was weaker; in briquette rupture stage,low-frequency electromagnetic signal amplitude and energy was dramatically strengthened. Frequency range of low-frequency electromagnetic radiation signal was located between 0 to 18 Hz,electromagnetic signal generated in the process of briquette rupture had a good low frequency characteristics and the changing amplitude and energy could well reflect the situation of briquette rupture.更多还原