Fatigue Life Analysis And Structural Topology Optimization Of Truck Frame

Taking a truck frame as the research object,the finite element static analysis,random vibration analysis,fatigue life analysis and structural optimization design of the truck frame are carried out.The research results can provide certain reference and guidance for the structural design of the truck frame.Firstly,the CAD model of the frame is established by using SolidWorks three-dimensional software,and the finite element model of the frame is established by importing the CAD model of the frame into HyperMesh software.For three typical limit conditions of full-load bending,full-load torsion and full-load bending and torsion,the finite element static analysis is carried out respectively,and the stress and strain nephograms of the frame under three typical conditions are obtained.Then,the static strength of the frame is checked.The first ten natural frequencies and modes are obtained by modal analysis of the frame,and the dynamic characteristics of the frame are preliminarily evaluated.Then,using Workbench software as the analysis tool,the finite element model of the frame is established.According to the grading standard of national standard vehicle pavement and the power spectral density of road roughness,the random vibration of the frame under random excitation of road surface is calculated by modal superposition method.The stress distribution and displacement amplitude of the frame random vibration are obtained,and the vibration characteristics of the frame are obtained.Then,using n Code fatigue analysis software,the ideal symmetrical cyclic load history,the finite element static analysis results of the frame and the S-N curve of the frame material are input into the fatigue analysis software.The S-N fatigue life analysis of the frame under quasi-static conditions is carried out,the fatigue life of the frame under three typical working conditions is calculated.The fatigue life cloud diagram of the frame is obtained,and the dangerous node of the fatigue life of the frame is found.Finally,based on the theory of structural topology optimization,the initial model of topology optimization is established by using the relevant parameters of the original frame.The objective function is to minimize the flexibility of the frame,and the constraint condition is the volume ratio of the frame.Topological optimization design of the frame under three typical working conditions is studied,and the optimal distribution results of the frame material are obtained.According to the results of the optimal distribution of the frame material,the frame was improved accordingly.The dynamic and static state of the frame before and after the improvement were analyzed and compared,which provided a basis for the optimal design of the frame.