Research on multi-layer spiral spray dust removal technology in heading face

In order to solve the problem of respirable dust pollution in the heading face, a multi-layer spiral spray dust removal method was proposed, in which supersonic pneumatic nozzles were arranged in a spiral shape. Taking the heading face of Qipan Coal Mine as the research object, the three-dimensional numerical model of multi-layer spiral spray dust removal technology device was established by using discrete element and finite element method and k-ω turbulence model and fluid flow particle tracking model in COMSOL software. The velocity field of multi-layer spiral spray air flow, velocity section and trajectory of water mist particles were obtained. The simulation results show that the airflow velocity at the cutting head of the TBM is faster, the farther away from the cutting head, the smaller the airflow velocity, and the airflow near the cutting head is very disorganized; after the nozzle is opened, the water mist particles will form a multi-layer spiral fog curtain, and the spiral fog curtain will cover the entire simulated driving surface after 20 s, and the particle size of the water mist particles is smaller than that of the traditional spray method.