Design And Experiment Of The Paddle-unloading Feeding Equipment For Pig-feeder

At present,the intelligent precision feeding technology is gradually being promoted and applied in large-scale pig farms.As a basic essential equipment for the feeding tec hnology,the superiority of the feeder performance directly affects the quality of feeding and growth performance of pigs.However,the feeding equipment of the intelligent feeder is prone to problems such as unstable discharge volume,uneven discharge,and arching and clogging during feeding operations,where there are few researches on in-depth structural innovation design and discharging process analysis.To this end,this research analyzes the current research status of feeders at home and abroad and their structural design advantages,and comprehensively utilizes theoretical analysis,virtual simulation research,high-speed camera technology,bench experiment and other methods to develop the research on the discharging performance of the paddle-unloading feeder equipment,focusing on analyzing the flow characteristics and movement laws of pellets during discharging process.The main research conclusions are as follows:(1)The research on the characteristics of pellets for pigs.Through independent design and construction of experimental equipment and the basic experimental methods,the characteristics of pellets are measured such as the geometric size and density of pellets,the static and rolling friction factor among pellets as well as between pellets and various materials,the angle of repose,internal friction angle,shear modulus of pellets and the restitution coefficient among pellets as well as between pellets and various materials,which can provide basic data for setting parameters in subsequent virtual simulation research.(2)The design and analysis of the paddle-unloading feeding equipment for pig-feeder.The overall structure,working process and principle of the feeding equipment were explained,focusing on the design of the hopper,arch-destroying unit,unloading unit,and establishing the kinematics and dynamics model of the discharging process of the feeding equipment.In-depth analysis of the pellet flow and movement process during discharging process is explained,and the structure optimization of the key components of the feeding equipment is given,determining the reasonable range of various parameters that affect the working performance of the feeding equipment to improve the feeding performance and efficiency of the feeding equipment.(3)Simulation analysis of the discharging process of the paddle-unloading feeding equipment for pig-feeder.The three-dimensional model of the feeding equipment and the pellet model were established and the discrete element software EDEM is used to simulate and analyze the discharging process.One is to explore the flow characteristics of the inclined rod-rope arch-destroying unit disturbing pellets in the hopper,and deeply explain the principle of preventing the arch formation.The other is to explore the laws of the movement of pellets affected by the unloading unit,analyzing the changing process of the movement trajectories of pellets,and clarifying the principle of improving the discharging rate and uniformity.Taking the established paddle-unloading feeding equipment as the research carrier,the high-speed camera technology was applied to track and capture the movement trajectories of pellets acted by the arch-destroying unit and unloading unit,verifying the correctness and reasonability of the theoretical analysis and virtual simulation research.(4)Experiment of the discharging performance of the paddle-unloading feeding equipment for pig-feeder.Taking the established feeding equipment of feeders as the research carrier,one is to carry out the arch-destroying performance experiment,selecting the hopper fill ing rate as the experimental factor,and using the discharging stability(expressed by the standard deviation of the discharging rate)as the evaluation index for single factor experiment,where the experiment results show that the standard deviation of the discharging rate obtained under different hopper filling rate is less than 4.00g/s,indicating that the inclined rod-rope arch-destroying unit makes the feeding equipment in good discharging stability.The other is to carry out the discharging performanc e experiment of the feeding equipment,selecting the rotational speed of the paddle,the discharging outlet distance,and the maximum backward inclined angle of the paddle discharging section as the experimental factors,and using the discharging rate and the discharging uniformity(expressed by the coefficient of variation)as the evaluation index for multi-factor experiment analysis.Meanwhile,the model is optimized based on Design-Expert 8.0.6 software,where the optimal parameter combination is obtained under the condition of the hopper filling rate of 80%: When the rotational speed of the paddle is 55.4r/min,the discharging outlet distance is 14.7mm,and the maximum backward inclined angle of the paddle discharging section is 31.3°,the corresponding discharging rate is 161.12g/s,and the coefficient of variation is 4.01%.The prototype of the paddle-unloading feeder is designed to verify the optimization results,and the experimental value is basically the same as the optimized value,which verifies t hat the designed feeder has a reasonable structure and good working performance.