Study On Thinning Flow Characteristics And Blockage Detection Method Of Feeding Pipeline

The method of thin feed feeding has been widely used in pig breeding,and the transportation of thin feed is mainly carried out by pipeline.Since the thin feed is prepared by mixing dry feed and water in a certain proportion,the dry feed needs to be pulverized,and the water absorption of the pulverized dry feed becomes stronger,which is prone to deposition,and is prone to blockage failure during pipeline transportation.In this thesis,based on the existing pig farm thinners ratio and pipeline structure,the CFD-DEM method is used to explore the flow characteristics of the thinner feeding pipeline,and the vibration modal method is used to explore the blockage of the pipeline.The conclusions of this thesis are as follows:(1)A numerical simulation model of solid-liquid two-phase flow was established based on the CFD-DEM method.By comparing the simulation data with the physical experimental values,it was found that the simulated simulation values were highly similar to the physical experimental values,which verified the rationality of the 3D simulation model in this thesis.(2)Using the established model to simulate the flow of thin feed in the horizontal elbow.The effects of different concentrations,different conveying speeds and different particle sizes combination on the movement of fluid and particles were studied.The results show that the maximum speed of fluid and particles mainly occurs at the inner side wall of the elbow,and the flow out of the elbow tends to be stable;The particles start to have angular velocity after entering the elbow,and some particles continue to the outlet of the pipe;the particles are greatly affected by the fluid force and occur at the elbow.When the particles flow out of the elbow,the force of the particles tends to be stable until the outlet of the pipe.The particle volume fraction distribution of the section at the elbow is starts from the 45° section,the particles are concentrated to the outer side wall of the elbow,and the volume fraction distribution of the particles is symmetrical.(3)The vibration modal method is used to analyze the blockage of the pipeline,and the modal simulation of the pipeline is carried out through the Workbench in the ANSYS software.It is compared and analyzed that the experimental results are basically consistent with the simulation results,and the mode shape characteristics are basically consistent.The natural frequency of the pipeline gradually decreases with the increase of the deposition amount in the pipe,and the corresponding relationship between the deposition amount and the natural frequency can provide a reference for the blockage of the pipeline.