工作面煤壁振动信号分析

Analysis of coal wall vibration

为研究综合机械化采掘设备工作对煤壁的扰动信号,探讨机械工作扰动对煤体破碎的作用,利用煤机装备试验系统采集了不同工况下煤壁的振动信号,采用希尔伯特黄变换对煤岩体受迫振动信号进行了模态分离和信号重构,并通过PFC2D模拟了煤壁振动信号对高能位煤岩的诱导破坏作用。研究结果表明:煤壁自振信号没有明显的载波特征,能量较低;采煤机直行割煤与斜切进刀扰动信号主要集中在低频阶段7~12 Hz,表现为低频诱导煤岩作用;低能量扰动能诱导高能位煤体发生破坏,有利于提高深部煤岩的破岩效率。研究结果对深部煤体低能耗截割理论的发展与完善具有重要意义。

In order to study the disturbance signal of the comprehensive mechanized mining equipment on the coal wall during the mining period and the effect of these disturbances on coal fragmentation,the vibration signals of coal wall under different working conditions were collected by the coal machine equipment test system in the State Energy Excavating Equipment R&D Testing Center.The vibration signals of coal body was reconstructed and its mode was separated by Hilbert Huang transform.The PFC2D model was established to simulate the induced damage effect of coal wall vibration signal on high-energy-potential coal.The results show that:the coal wall vibration signal has no obvious carrier characteristics,and its energy is low;the disturbance signal of straight cutting and oblique cutting of shearer mainly concentrates in the low-frequency stage of 7-12 Hz,which shows the low-frequency induced coal fragmentation.The small disturbance energy induces the destruction of high-energy-potential coal body,which is beneficial to improve the coal breaking efficiency of deep coal.The research results are of great significance to the theory of low energy consumption cutting of deep coal.