Study On Pipe Flow Characteristics Of Coal Gangue-based Filling Slurry And Its Flow-induced Mechanical Response Characteristics Of Conveying Pipeline

Coal filling mining has become an important technical way for the disposal of coal gangue and other mining solid wastes on a large scale,and the paste filling coal mining method is the latest generation of filling technology,which sends the coal gangue-based filling slurry into the underground mining area through the pipeline system to achieve green mining.For the gangue-based filling slurry pipe flow law is unknown and its long distance and high flow rate transport induced significant mechanical response of the pipeline and other difficult problems,around the filling slurry rheological principal structure and pipe flow law and other scientific issues,the comprehensive use of theoretical analysis,numerical simulation and indoor experiments and other methods,the establishment of the gangue-based filling slurry fractional order rheological principal structure equations,based on this study to obtain the filling slurry pipe flow law,proposed filling The flow discriminatory criterion of the slurry,revealing the mechanical flow-energy response characteristics of the gangue-based slurry transport pipeline.The main research results are as follows:(1)The fractional order calculus and fractional order rheological components are introduced to improve the traditional integer order rheological model,and the fractional order rheological model is proposed to reflect the rheological characteristics of the paste-filled slurry more realistically,and the proposed fractional order rheological model is verified by rheological experiments,and the results show that the fractional order rheological model can effectively compensate for the deficiencies of the integer order rheological model and can better describe the rheological characteristics of the slurry.(2)The rheological properties of coal gangue-based filling slurry were tested by rotary rheometer,and the effects of slurry concentration,fly ash content and cement content on the rheological properties of slurry were investigated.The microscopic influence mechanism of the above factors on the rheological properties of slurry was analyzed.The variation of rheological parameters of slurry with slurry concentration,fly ash content and cement content was obtained.(3)Based on the fractional-order rheological model of the filled slurry,a comprehensive analysis of the tube flow law of the gangue-based filled slurry is carried out by hydrodynamic theory,and the expressions for the flow distribution,flow rate,average flow rate,differential pressure and Reynolds number of the slurry are obtained,and the fractional-order slurry flow discriminant criterion is proposed;and the tube flow characteristics of the gangue-based filled slurry are studied by numerical simulation,and the effects of the slurry flow rate,pipe diameter and bend radius on the flow characteristics of the slurry are obtained,The influence of slurry flow velocity,pipe diameter and bend radius on the flow behavior of slurry pipe was obtained.(4)The Ansys software was used to study the flow-induced mechanical response characteristics of the filling slurry pipeline through numerical simulation.The influence of coupling calculation method,slurry flow rate,pipeline wall thickness and elbow radius on the flow-induced vibration characteristics and fatigue failure characteristics of the pipeline was analyzed.The influence of slurry flow rate,gangue particle size,gangue particle mass flow rate and gangue particle shape on the erosion wear characteristics of the pipeline was analyzed.This thesis has 112 figures,42 tables,116 references.