Discrete Element Simulation Study On Material Conveying Process Of Bucket Elevator

In the food industry,building materials and other fields,the use of bucket elevators to achieve material handling has certain advantages.Meanwhile,under the continuous development of computer technology,the application of simulation technology based on discrete element theory in various industries has accelerated the informatized and intelligent development of material handling equipment.Due to the lack of deep understanding of the mechanism between the action of materials and the mechanical equipment,and the lack of theoretical basis for the design of equipment parts,it is imperative to study the dynamics of materials and the mechanism of action of the hopper.It also provides a basis for structural optimization of bucket elevator components.Because the contact characteristics of the material and the hopper are generally characterized by the movement behavior of the material and the force form of the hopper,in order to explore the interaction mechanism between the material and the hopper,this paper analyzes and infers the forced state of the material during the loading and unloading stages.Based on the equation of motion,the three-dimensional model of material loading and unloading was established by means of discrete element simulation software EDEM and the simulation calculation was carried out.Through the analysis and processing of the results,the data and conclusions with certain reference are obtained.The main research contents and conclusions include:Firstly,from the perspective of the theory of granular mechanics,the forced state of the material in the loading process is analyzed and the equilibrium equation is established;The three unloading modes in the unloading process and the slip surface characteristics of the material moving in the hopper are derived;Under the premise of the assumption,the material slip force balance equation is established and solved;According to the movement characteristics of the material,the method for judging the initial discharge angle of the hopper and the material emptying check is determined,and the equation of the motion path after the material is discharged is given.Secondly,the discrete element simulation of the material loading was carried out,and the motion form and velocity distribution characteristics of the materials at different positions were observed and compared,and the material loading and movement speed changes under different bucket speeds were statistically compared;Under the given material sampling conditions,the velocity distribution characteristics of the material at the hopper mouth,front wall and side wall are statistically stated;The contrast characteristics of the material and the hopper are explained in comparison at different bucket speeds;The strength distribution characteristics of the hopper structure are obtained by establishing the coupling calculation of the hopper strength.Finally,the unloading of materials is similarly simulated by EDEM.The velocity and shape distribution of materials at different positions are observed,and the flow patterns of materials under different bucket velocity and bucket type are compared;At different bucket speeds,the material trajectory envelope and velocity changes were compared and analyzed;The material at the front wall of the hopper and the surface of the pile was taken as the object,and the distribution characteristics of the velocity were statistically described within a given range;under different bucket speeds and bucket types,the spatial position distribution characteristics of material flow are statistically showed;At different hopper speeds and types,material unloading performance of each hopper is statistically analyzed,and the combination of the best and worst parameters of the unloading effect is given.