CFD-based Solid-liquid Two-phase Flow Pattern Analysis And Resistance Loss Model Research

My country is rich in mineral resources,but mostly distributed in remote mountainous area,Using railway,highway,etc to transport not only costing large investment,long construction time but also causing serious damage to the environment.More and more people pay attention to the Pipeline transportation because of its low cost,high efficiency,small footprint and low pollution.When the pipeline is used to transport the slurry,the resistance characteristic of the pipeline is one of the key problems in the pipeline transportation technology,which directly affects the choice of transportation pressure of the whole pipeline system,the number of pump,the number of pumping stations and the pipe material and pipe wall thickness,which plays an important role in the design of the whole pipeline transportation system.Therefore,it is very important to study the resistance characteristics of slurry pipeline transportation.In addition,the pipeline in the process of laying due to the limitation of geographic location,ups and downs,big difference,is no longer level laid but presents gradient of slope laid.Therefore,studying on the characteristics of complex shape pipeline.is particularly important.However,due to the complexity of the flow of solid-liquid two-phase flow,it is quite difficult to carry out purely theoretical research.The research is always based on the experiment,not only cost a lot of manpower,material resources and time and get the empirical formula,restricted by experimental conditions.This paper based on the solid liquid two phase flow theory,combined with computational fluid mechanics principle,to carry out numerical simulation and analysis on the pipeline transportation by computer.The main research work of this paper is as follows:(1)Based on the study of basic physical properties and slurry properties of solid materials,The mechanism of the internal movement of the solid materials and the slurry was studied which provides the basis for the subsequent numerical simulation of the experimental parameters.(2)According to Computation Fluid Dynamics,the numerical simulation of pipeline transportation is carried out by using the Fluent software based on the multiphase flow model-Euler model,discussing change law of the slurry velocity distribution and particle concentration distribution at the outlet under the different pipeline flow velocity,particle concentration,particle size,particle density,pipe diameter and angle,moreover analyzing the variation law of resistance loss under different working conditions,which provides a good reference value for engineering practice.(3)By analyzing the flow law of solid particles under different working conditions,the main sources of pipeline resistance loss are obtained.Through the analysis of the results of numerical simulation,the expression of the relationship between the various transport factors and the resistance loss is fitted.Acoording to the energy theory,the horizontal and inclined pipe resistance loss calculation model are proposed based on dimensional analysis.Finally,the model is validated by the measured data.The results show that the calculated values of the model are in good agreement with the measured resistance loss,and can accurately predict the resistance loss of the pipeline,Which provides some reference value for the prediction of the resistance loss of solid-liquid two-phase flow pipeline.In this paper,the combination of theory and experiment are be used to carry out research.Based on the energy theory and the principle of computational fluid mechanics,the numerical simulation and analysis of pipeline transportation are carried out by using the computer.The method is not only convenient and fast,but also can be used to observe the flow pattern within the pipeline,which provides a certain practical significance to the actual project.