Research on impact recognition mechanism of coal gangue and the tail beam based on vibro-acoustic multi-physical field coupling simulation

Integrated mechanised roof coal mining is an important mining method for extra thick coal seams, most of the current coal release studies are still stuck in mechanical analyses, the vibration difference caused by its contact response makes it difficult to identify gangue efficiently and accurately in complex environments. Aiming at the lack of research on the mechanism of difference of single medium under different coal discharge conditions, this paper proposes a research method of identifying the impact response characteristics of coal gangue under vibration-acoustic multi-medium. Firstly, the coupled vibro-acoustic multi-physical field simulation model is constructed based on the vibro-acoustic propagation theory; Secondly, it analyses the difference in vibro-acoustic response induced by the inherent difference in gangue, comparison of vibration and acoustic signals after coal and gangue impacts on tailing beams through, verification of the feasibility of vibro-acoustic signals as a basis for gangue identification; Then study the vibration-acoustic response law of gangue collision with tail beam under different impact positions, analyse the stress distribution at different locations of the tail beam after impact to reveal its vibration differences and the propagation of vibration-generated sound under the spatial location; Finally, the vibration acceleration and sound pressure are compared and analysed under three working conditions: different coal discharge heights, different particle diameters and different coal discharge angles, the vibration-acoustic response law under different coal discharge conditions was obtained, which provided a research basis for the subsequent coal gangue identification study.