Study On Transportation Characteristics And Resistance Loss Of Filling Slurry In Multi Dip Pipeline

Pipeline transportation is the core link in the coal gangue slurry filling project in coal mines.Due to the extremely complicated pipeline system during the transportation process,in order to ensure the safety and efficiency of the transportation process,it is necessary to conduct in-depth research on the motion mechanism of the slurry in the pipeline.Analyzed and solved the pipeline transportation performance problems related to the slurry’s pipeline transportation characteristics and resistance loss.In this paper,taking the actual filling pipeline of a coal mine as the background,comprehensively using theoretical analysis,numerical simulation and other means to study the transportation characteristics and resistance loss of coal gangue filling slurry in complex multi-dip pipelines.The main work and research The results are as follows:(1)The numerical model of coal gangue-filled slurry pipeline transportation under the actual engineering background was established by using Fluent software to explore its transportation characteristics and resistance loss changes.The results show that: the larger the slurry inlet velocity is,the higher the velocity gradient of the outlet section of each local elbow is.and the gradient difference between the 150 mm pipe diameter and the other two pipe diameters is relatively small,that is,the flow process is relatively stable.When the inlet flow rate under each pipe diameter is greater than 1.4m/s,the gradient expansion rate is accelerated;when the pipe diameters are 130 mm and 150 mm,the resistance loss increases with the increase of the slurry mass concentration;when the pipe diameter is 180 mm,the resistance loss first increases and then decreases,and reaches the maximum value whenω=78%.(2)Using Fluent software to establish a multi-particle size gradation numerical model for coal gangue-filled slurry pipeline transportation under the background of actual engineering to explore its transportation characteristics and resistance loss changes.When the diameter gradually increases,the volume concentration distribution of coarse particles changes significantly.When the particle size of the coarse particles is from 5 mm to 7 mm,the coarse particle phase gradually extends from the bottom of the pipe to the center of the pipe,forming a plug flow;With the gradual increase of the particle size of the fine particles,the sedimentation phenomenon at the bottom of the pipeline in the coarse particle phase becomes more and more obvious,that is,the sedimentation amount of the gangue increases.(3)Using Matlab software to build BP neural network algorithm to predict the resistance loss along the pipeline transportation and the local resistance loss of the bending pipe in this mine.The research results show that: using genetic algorithm to optimize the traditional BP neural network model,the model After training,the relative error of the predicted value of resistance loss along the route is up to 11.9%,the average relative error is 6.7%,the relative error of the predicted value of local resistance loss of the elbow is up to 15%,and the average relative error is 4.8%.Compared with the traditional BP neural network,the prediction accuracy is greatly improved.(4)Using SPSS software to conduct sensitivity analysis and significance analysis,it is concluded that the sensitivity order of each influencing factor to the resistance loss along the route in the mine background is: inlet flow velocity > pipe diameter > mass concentration;The sensitivity order of resistance loss is: elbow angle>inlet flow velocity>pipe diameter>mass concentration;pipe diameter,slurry mass concentration,inlet flow velocity and elbow angle all have a highly significant effect on the resistance loss value.