Simulation Study On The Flow Characteristics Of Coal Gangue Paste Adhesive Filling Slurry In Pipeline

Coal,as a basic energy source,plays an important role in human progress and national economic development,Filling mining not only has a high recovery rate,but also can effectively control surface subsidence and protect the ecological environment of mining area.It is an important technical way for coal enterprises to realize green mining.In the design of filling system,the flow characteristics of filling slurry directly determine the filling efficiency.Therefore,theoretical exploration and Research on slurry flow characteristics in pipeline has important theoretical significance and practical value.In this paper,according to the flow characteristics of coal gangue gypsum cemented filling slurry in pipeline,combined with the slurry ratio and slurry rheological model given by other researchers,according to the actual working conditions of the project,the slurry transport characteristics were simulated,the effects of velocity,pip e diameter,pipe inclination angle,slurry concentration and pipe bending radius ratio on slurry flow in filling pipeline were studied by using CFD.The main research contents are as follows:1.For horizontal straight pipe,the distance required for slurry flow to reach stability increases and the pressure difference between inlet and outlet increases with the increase of slurry inlet velocity;When the pipe diameter increases,the distance required for slurry to achieve steady flow increases and the pressure difference decreases;When the slurry concentration increases,the pressure difference between the inlet and outlet of the pipeline increases accordingly.2.When the inclination angle a of the straight pipe changes from-30° to 30°,the pressure difference between the inlet and outlet of the pipe increases with the increase of a.3.When the ratio of bending radius to radius of pipeline increases,the deviation of maximum velocity position to the outer wall of pipeline decreases,the wear on the outer wall of pipeline in bending section decreases,and the pressure difference between inlet and outlet of pipeline increases.4.In the entrance section,the volume fraction of coal gangue particles varies with the increase of distance from the entrance.L=12m is the shortest distance required for the stable distribution of coal gangue particles at different entrance velocities and concentrations;When the inlet velocity is greater than 1.6m/s,the concentration of coal gangue particles is stable,and the volume fraction of coal gangue particles in most areas of the cross section of the pipeline is approximately uniform.