Numerical Simulation Study On Coupling Of Fully Mechanized Face Slope And Coal Slip With Double Dust Sources In Tashan Coal Mine

The impact airflow caused by coal wall,the movement of scraper conveyor and its rebound effect on dust will produce a large amount of dust,resulting in dust pollution on the working face,seriously affecting the underground working environment,damaging workers' health and reducing work efficiency.This paper takes the fully mechanized mining face of Tashan Coal Mine of China Coal Group as the research object,adopts the research method of combining theoretical analysis and numerical simulation,studies the migration law of impact air flow and dust,and analyzes a series of related factors affecting impact air flow and dust concentration.The research contents and main conclusions of this paper include the following points:(1)The generation mechanism and influencing factors of mining face dust are studied.According to the conservation law and the relevant theories of hydrodynamics,firstly,the flow law of continuous phase air flow is obtained by building the N-S equation.Secondly,the stress of working flour dust is analyzed and the motion equation of discrete phase dust particles is established.According to the analysis of the general situation of the fully mechanized mining face,Gambit software is used to establish the geometric model of the fully mechanized mining face,mesh and set the initial boundary conditions such as wall and velocity entrance.(2)Set the solution parameters of the equation in fluent,and carry out the numerical simulation of the air flow under different conditions.The distribution characteristics of the continuous phase air flow on the working face,the impact of the impinging air flow on the working face after different times of the wall and the impact law of the wall with different quality on the working face air flow are obtained.It is concluded that when the air flow does not flow through the obstacles,the wind speed distribution is uniform and the size is maintained at 2.06 m/s.When passing through obstacles such as shearers,the wind speed vector deflects,and the maximum wind speed reaches 2.82 m/s.The panel will increase the wind speed of the working face,and the impact air flow generated by different panel quality will have the same impact on the air flow of the working face within the same time.(3)Under different parameters in the DPM model,by selecting the interaction between air flow and dust at a certain time,the dust concentration of working flour when the scraper conveyor and the upper dust source act alone and the dust concentration under the coupling of the two dust sources are compared when t = 8 s.It is found that the dust concentration during coupling has an obvious accumulation phenomenon,and the diffusion distance of dust along the Y axis is 2.5 m when the two dust sources act.By analyzing the dust distribution law of the double dust source coupling of the sidewall and the coal chute in the fully mechanized mining face,it can be obtained that the key areas of dust prevention and control are the tunnel space formed by the coal wall and the shearer,the shearer drum,the outside of the coal chute baffle and the air outlet of the working face.The paper has 25 pictures,10 tables,and 76 references.