Research On Drag Reduction And Shovel Loading Strategy Of Loader Based On EDEM

Wheel loader is a relatively common construction machinery in production and life,and its high efficiency and energy saving in the process of shovel loading have gradually become the research direction pursued by people.In actual working conditions,the shovel loading operation of the loader puts forward higher requirements for the driver’s operation.During the shovel loading process,the shovel loading resistance will increase the wear of the loader tires,reduce the operation efficiency,and cause energy waste.Therefore,it is of great practical significance to realize the drag reduction and shovel loading of the loader.Relying on the school-enterprise cooperation project "Development of 5t Wheel Loader"（Project No.:FW/RD201640）,in the theoretical research stage,this paper studies the shovel loading mechanism of the loader,including the shovel loading operation process and theoretical basis,that is,the compact verification theory and the slip surface principle.Afterwards,theoretically deduce the force of the bucket during the shovel loading process of the loader,the variation law of the shovel loading resistance,and the determination of the shovel loading resistance component.According to the results,the drag reduction mechanism and implementation method are proposed,that is,the preliminary drag reduction strategy: When the shovel loading operation reaches a balanced state,the purpose of breaking the balanced state is achieved by changing the movement posture of the working device,that is,raising the boom for a certain distance.Finally,the factors that affect the shovel resistance are analyzed,including material type,material particle size,material stack height,etc.,which lays the foundation for the subsequent discrete element simulation and the proposal of the optimized drag reduction strategy.By analyzing the physical and mechanical properties and contact properties of bulk materials,the EDEM software platform is used to model different materials,and the loader shovel operation is simulated and analyzed based on the EDEM platform.According to the results,an optimized drag reduction strategy is proposed: shovel loading When the operation reaches a balanced state,different materials shovel loaded correspond to different lifting distances of the boom.The larger the particle size of the shovel loaded material,the greater the lifting distance,so that it can continue the shovel loading operation and improve the operation efficiency.Then,the discrete elementmultibody dynamics simulation（DEM-MBD co-simulation）was carried out using EDEM and Recur Dyn software platform,and the rationality of the optimized drag reduction strategy was verified.For the proposed optimized control strategy,the electro-hydraulic proportional control technology mechanism is used to study,and the load spectrum experiment is carried out on the real vehicle.The criterion for realizing the optimized drag reduction strategy is obtained through the load spectrum experiment,that is,the drag reduction strategy is implemented based on the difference between the torque required by the accelerator pedal and the actual torque of the engine（based on the torque difference）.specific implementation.Then,based on the AMESim platform,the hydraulic system model of the loader working device was built and simulated to verify the implementability of the strategy.The simulation results were optimized by the PID controller built in Simulink,which laid the foundation for the actual vehicle experiments in the following.The actual vehicle experiment was carried out with a certain model of the schoolenterprise cooperation project,which verified the feasibility of the strategy and effectively improved the efficiency of shovel loading.And in the in-depth research,it is verified that the power used in the shovel operation using the drag reduction strategy proposed in this paper is reduced compared with the traditional one-time shovel method,and it is more energy-saving and environmentally friendly,which is a good way for the follow-up construction machinery drag reduction operation.Research provides some references.