Propagation Features of Channel Wave Signal in Coal Seam with Scouring Zone

Abstract

This paper mainly analyzes the typical geological structure of the coal seam with scouring zone, and examines the channel features of the coal seam. Firstly, a detailed analysis was conducted on the propagation features of channel wave in complex coal seam with geological anomalies. Based on COMSOL Multiphysics, a three-dimensional (3D) medium geometry model was established for complex coal seam with scouring zone. Relying on the model, channel wave propagation was simulated by finite-element method, and the propagation features were analyzed thoroughly. The Ricker wavelet with a central frequency of 200Hz was employed to emulate the explosive source, and the excited vibration signal was measured along the coal seam. Experimental results show that the longer the propagation distance of the channel wave signal in the coal seam, the more stretched the channel wave train, and the later the arrival of the maximum envelope of the wave train. The maximum envelope of the wave train appeared earlier in the model with the scouring zone than in the model without the scouring zone. After the channel wave passed through the scouring zone, the maximum envelope of the wave train appeared later in the model with the scouring zone than in the model without the scouring zone.