Experimental Research on Diffusion and Mitigation Law of Dust Cut Generated by Coal Shearer

It is known that the vortex wind flow, which is formed from the rotation of rotary drum of coal shearer, is the direct factor to cause the diffusion and mitigation of dust. The experimental measurement of the dust diffusion from coal cut was implemented at Chengzhuang Coal Mine's No.5306 full mechanized face in confined space and the basic law of diffusion and mitigation of cut dust under different conditions was analyzed. It is concluded that, for either downwind or upwind coal cutting, the role of vortex wind flow field in cut dust mainly occurs in the lower one fourth circular zone of the rotary drum beside the coal shear. The concentration of respiratory dust in the zone could be 95 mg/m<sup<3</sup< under downwind coal cutting and 110 mg/m<sup<3</sup< under upwind coal cutting. Both of them are far higher than the requirements of national standard.