The Simulation Analysis And Process Parameters Optimization Of Corn Threshing Cleaning

Due to the complexity of the threshing and cleaning process of the corn,the traditional methods for such process are not only a waste of time,but also a waste of financial and material resources.And the results obtained are not universal which has a great difference from the actual threshing and cleansing process.By using the method of discrete element to study the process of threshing and cleaning,it is not only observes the materials movement directly,but also solves problems of repeating experiments,long manufacturing cycle and low efficiency in the traditional mechanical design process.This method achieves the purpose of saving the cost of mechanical design.In this paper,the device of the self-propelled corn cleaning and threshing machine4YZL-5 is used as the research object.The method of SolidWorks is used to establish the geometric simulation analysis model of the threshing and cleaning process.This method introduces the structure and working principle of the device in cleaning and threshing process.At the same time,it analyses the main influenced factors of the device.In this paper,Zhengdan 958 maize variety is used as the research object.SolidWorks is used to model the components of crops,and imports it into discrete software EDEM.The spherical particles filling method is used to establish a simulation analysis model of corn threshing and clearing.The density of corn explants is measured by cylinder drainage.The mechanical contact parameters of the corn explants are analyzed effectively and reasonably valued.The basic principle of the discrete element simulation of threshing cleaning has been studied in depth,which mainly describes the functional characteristics of discrete element software and the solution process of discrete element method.The contact mode and contact model between the particles in the threshing cleaning process were analyzed.At the same time,theoretical analysis of simulation time steps are used,which detemines the time step of the simulation of the corn threshing cleaning process.The rate of taking off is used as the indicator.Orthogonal test was used to optimize threshing process parameters(rotation speed,feed volume and threshing clearance).The cleanliness rate and loss rate were used as test indicators.The parameters of the cleaningprocess were optimized using tests under single-factor conditions,including the vibration frequency,direction angle,and amplitude.The best combination of parameters were obtained through the clean test.The device of cleaning and threshing of the 4YZL-5 grain combined harvester was used as a bench test platform,and a test bed test was carried out on the test bench to study the influence of different factors on the performance of threshing and sorting process of corn and the performance of the device of cleaning and threshing.The experimental results are compared with the simulation results,which preliminarily proves that the discrete element method is reasonable and effective for the simulation analysis of corn threshing and cleaning process.