Optimization Design Of Rubber Stack Structure Size Based On Parametric Modeling

The rubber pile is a load-bearing damping element connecting the locomotive body and the bogie,which directly affects the safety,stability and comfort of the high-speed rail operation.In its optimization design process,in order to determine the structural size of the rubber pile and the rubber hardness of the rubber material,it is necessary to repeatedly establish a finite element model.In order to shorten the development cycle and improve the accuracy of the rubber stack structure design,this paper takes the high-speed rail bogie rubber stack as the research object.Based on the secondary development function of ABAQUS software,the rapid modeling and result analysis module of the rubber stack is developed using Python language.The ABAQUS pre-processing and post-processing are automated;at the same time,in order to meet the stiffness and fatigue performance requirements of the rubber pile,the size of the rubber pile is optimized using Isight software,and the stiffness test and fatigue test results are combined to verify the reliability of the optimized structure of the rubber pile.The main research contents of this paper are as follows:1.Selection and parameter testing of constitutive models of rubber materials.In order to accurately calculate the stiffness and fatigue life of the rubber pile,on the basis of analyzing the characteristics and applicable scope of various rubber material constitutive models,the Mooney-Rivlin constitutive model suitable for small deformation is selected as the constitutive model of rubber material for finite element analysis.,And designed the mechanical test of rubber materials,and got the relevant parameters of the Mooney-Rivlin constitutive model.2.The secondary development of the rubber pile simulation analysis module and the design of the man-machine interface.Based on the script interface and object model of ABAQUS,the structure simulation module of the rubber pile is designed;combined with the structural parameters and material parameters of the rubber pile,the parameterized modeling of the rubber pile,the definition of material properties,the creation of contact properties,the application of loads,and the meshing are designed.And the script program of the process of outputting analysis results,realizes the automation of ABAQUS pre-processing and post-processing;using the RSG dialog box builder,designing the human-computer interaction interface for the parametric modeling of the rubber pile;and taking a high-speed railway rubber pile as an example,Using the developed pre-and post-processing program,the automatic generation of the finite element model of the rubber pile,the automatic output of the stress-strain cloud diagram and the stiffness curve are realized,which verifies the accuracy of the program.3.Research on optimization of rubber pile size.Taking the size parameters of the rubber pile and the rubber hardness of the rubber material as variable factors,an orthogonal experiment was designed to optimize the size of the rubber pile.The preand post-processing program developed was used to perform parametric modeling and stiffness calculation of the rubber pile,and The solution results are imported into the Isight software,and the size of the rubber pile is optimized using the multi-island genetic algorithm.The optimization results are: the stress of the rubber pile is reduced from 16.6 MPa to 13.9 MPa;the strain distribution is more uniform;under the design requirement that the product's optimal stiffness is 17.5 k N/mm,the stiffness is increased from 16.78 k N/mm to 17.45 k N/mm,Stiffness matching is better;the fatigue life is increased from 3.689 million times to 5.358 million times,and the life span is increased by 45%,which meets the fatigue resistance requirements of the product.4.Test verification of rubber pile structure.Based on the optimized rubber stack structure,a test sample was manufactured,and the sample was subjected to vertical stiffness test and fatigue test.The test result is: the vertical stiffness value is17.28 k N/mm,which is compared with the stiffness obtained by the optimized simulation(17.45 k N/mm)difference of 1%;fatigue life is 5.9 million times,which is10% difference from the fatigue life calculated by Endurica software(5.358 million times).The test results are basically consistent with the simulation analysis results,verifying the optimal design of the rubber stack Accuracy.