Research On Model Library And Virtual Simulation In Intelligent Design Of Rice-wheat Cleaning Device

As an important part of the rice-wheat combine harvester,the cleaning device not only directly reflects its working performance,but also affects its operating efficiency.Therefore,the design and optimization of the cleaning device has always been a hot topic of research.However,the traditional method has some disadvantages like low design efficiency and long design cycle.The intelligent design method makes high-efficiency,high-quality,diversified and customized design possible.The establishment of the key parts model library and virtual simulation are very important in the process of intelligent design.In order to solve the problem of lacking key parts model library and the fact that the virtual simulation results cannot be used for design basis directly,this article designed and developed a key parts model library with the help of NX design software,also measured the relevant physical parameters of operation objects,and then conducted some virtual simulation and proving experiments.Finally,this article realized the optimization of component parameters under given conditions through combining the model library and the simulation in the intelligent design system.The main research contents of this article are divided into the following parts:(1)The establishment of a parametric model library of cleaning device.The establishment of key parts’ parametric model library of cleaning device.The structural characteristics of the cleaning device were determined by consulted domestic and foreign literature,design manuals,product drawings and other technical data extensively.Having used C ++ and KF(knowledge fusion)in Visual Studio 2012,redeveloped the NX software.Through obtaining the relevant parameters in the design process of the cleaning device parts,established the key parts’ parametric model library of cleaning device in the intelligent design system,including fish scale screen,fan,shaking plate,and mesh screen.(2)Experimental research on the physical parameters of rice.The physical parameters that need to be set in the simulation of the cleaning process was analyzed.Having taken the rice extracts threshed by the threshing device as the object,measured the geometric size,suspension speed,repose angle,density,and recovery coefficient of each component.(3)Simulation and test verification of the interaction between cleaning device and rice.Having taken three kinds of materials,grains,short stalks and long stalks,as the objects,the numerical simulation of impurity rate and loss rate was carried out by EDEM and Fluent hydrodynamic coupling method,and the gas-solid two-phase flow coupling simulation was carried out by Euler model.Then designed and built a clear test bench to verify the simulation results through the bench test,and the relative error of most experimental data was about 10%.The experimental results show that the simulation of the impurity rate and loss rate based on fluid-structure coupling simulation has highly accurate degree.(4)Model,simulation and optimization in intelligent design system.Useing the existing intelligent design system of the cleaning device to generate relevant design parameters of the cleaning device.After that,the model library generated relevant model instances by calling these parameters.Then conducted simulation tests and optimization design with the help of the cleaning simulation system.Finally,imported the model into instance library.