Analysis Of Drive Axle Housing Fatigue Life Based On Virtual Test Bench

Automobile durability is one of major indicators to evaluate car quality and has greateffect on automotive performance. As an important automobile part, the durabilityperformance of drive axle housing will affect the overall performance of vehicle.Therefore, it is necessary to predict the fatigue life of axle housing. Based on the modalanalysis theory and the modal stress recovery theory, finite element model and virtualtest model of the axle housing are built by software, and then the result of fatiguedamage and life are reached by analysis.Firstly, the research status on static analysis, fatigue analysis, test methods andevaluation indexes for drive axle housing indoor test were introduced. After that, asimplified model of the axle housing was built in Hypermesh. Based on the provisionsof the national standard, the statics analysis of axle housing was conducted by setting upconstraints at rigid area of bridge shell fulcrum and applying uniformly distributed loadon spring seat. The static stiffness and strength of axle housing was verified. Then, themodal analysis for axle housing was conducted and verified. The document which canbe analyzed by Nastran was exported.Secondly, after the calculation of Nastran, the flexible body of axle housing virtualprototype test rig was built in Adams/View, and the simulation of different frequenciesasymmetric cyclic load which amplitude was2.5times of the full load was conducted,which presented modal displacement and stress maximum points in correspondingworking conditions. Moreover, the maximum stress values and corresponding locationswere compared and a time-history file used for fatigue analysis was derived.Finally, the material characteristic curve of axle housing was established and thetime-history file was associated with the.op2file which was obtained from Nastran inMSC.Fatigue. Then the simulation of fatigue was submitted. The fatigue damage andlife of axle housing were obtained. The results of the research show that the staticstiffness and strength of axle housing correspond to specified requirements and the lifeof axle housing meets the design requirements. Besides, the fatigue damage and life ofaxle housing with the same load but different frequency are almost the same within acertain frequency range.