Abstract: In view of serious dust pollution problem in sloping road transfer point,the geometric modelling of the No. 3 transfer point of Qipanjing Coal Mine was carried out by using COMSOL software,and based on the particle tracking model of Computational Fluid Dynamics (CFD),finite element method,and k-ε turbulence model,the distribution of wind flow streamline, the distribution of velocity multicut section and the trajectory of dust particles in the No. 3 transfer point were computed, the changes of wind flow and dust transport law were investigated in the No. 3 transfer point during production work. The wind flow changes and dust transport law at the No. 3 transfer point during production work are studied,and a multi-section fog curtain dust control technology is proposed,which is based on principles of spiral fog curtain dust control and supersonic dust isolation, can form a long-distance and wide coverage fog curtain to wrap dust particles to maximum extent to achieve highly efficient purification of dust,and finally,through dust control experiments and on-site application of the technology at No. 3 transfer point of Qipanjing Coal Mine,the high efficiency of this technology in terms of dust reduction characteristics and reliability are verified. The study results show that:the wind flow distribution is mainly affected by combined effect of belt speed,traction and induced airflow,and is distributed in layers along horizontal and vertical directions,forming a dense vortex with an average speed of 0. 5 m/ s. Dust is easily affected by vortex spreading in all directions,it is mainly distributed on downwind side,the particles of sizes between 5 μm and 15 μm are more susceptible to diffusion of wind flow,and are gathered in height of the workers′ respiratory zones,which is seriously contaminated. After the dust control experiment and on-site application of this technology,the dust reduction efficiency of whole dust and exhaled dust is as high as 93. 65% and 85. 59% respectively.

Key words: transfer point,numerical modelling,multi-section fog screen,dust transport,dust removal efficiency