Analysis And Research On Air Velocity Of Long Distance Pneumatic Conveying System

In the process of long-distance pneumatic conveying system,there will be some problems that affect the normal transportation of material particles,such as serious pressure loss of the system,wear of pipelines,crushing of material particles,and blockage of pipelines.Among them,the wear has a very serious impact on the service life of the transportation pipeline and other components,and the excessive airflow velocity in the pipeline is the key influencing factor that causes serious pipeline wear.In this paper,the horizontal section of the pipeline is the main object of research.By designing and optimizing the size and structure of the pipeline to reduce the airflow velocity in the pipeline,the system can maintain a stable delivery state,so as to achieve the purpose of reducing pipeline wear.Aiming at the problem of pipeline wear in the long-distance pneumatic conveying system,the effects of the physical properties of the material particles and the airflow velocity in the pipeline on the abrasion of the pipeline were analyzed,and the effect of the airflow velocity on the pipeline wear in the pipeline was analyzed.Excessive air flow velocity in the pipe is the main reason for serious wear of the pipe.Therefore,in order to reduce the airflow velocity in the pipeline,this article mainly starts from the following aspects:First,based on the principle of equal pressure loss before and after diameter reduction,this paper optimizes the design of the structure of a single-diameter pipeline,that is,a way to gradually expand the diameter of the pipeline.And using the pressure loss calculation method,the design calculation formula of the diameter of the reduced-diameter pipe,the position of the reduced-diameter pipe and the reduced-angle angle are given.Second,theoretically design three schemes of single-diameter pipeline,firstgrade variable-diameter pipeline,and second-grade variable-diameter pipeline for comparative analysis,and obtain the optimal diameter of the reduced-diameter pipeline,the location of the reduced-diameter pipeline,and the variable-angle.Third,this paper is based on the principle of EDEM-FLUENT coupled simulation simulation(particle control equations followed by the discrete phase and gas control equations followed by the fluid phase,etc.),and according to the actual situation,the Euler coupling model is used to obtain the Pressure distribution,air flow velocity distribution and particle movement trajectory etc.Fourth,through the simulation results and comparative analysis with the calculation results,it is concluded that the airflow velocity in the secondary variable-diameter pipe is relatively stable and the pressure loss is minimum.It is verified that by optimizing the pipeline structure,the airflow velocity in the pipeline can be reduced,so that the system can maintain a stable delivery state,thereby achieving the purpose of reducing pipeline wear.