Structure Analysis Of Commercial Vehicle's Driving Axle House

As the development of lightweight of the vehicle, CAD/CAE becomes one of the key technologies in product design for fantastic durability. It makes full use of CAE technology in this paper to analyze the strength of structure and fatigue strength of axle house, which provides reasonable suggestion in coping with the issue of structure modification. The main jobs of this paper are as follow:Firstly, the 3D model and FE model of the rear axle house were established under CATIA and HYPERMESH platform respectively, which is the basic for the analysis.Secondly, According to the bench test method of the standard QC-T 533, bend stiffness and static strength simulation analysis of the axle house were carried out, which proved that the bend stiffness and static strength basically meet the requirements of QC/T534. And then the static strength was calculated under three kinds of load cases, including random road loading, maximum drawbar pull and emergency brake, the results show the map of high stress sections and provide reasonable suggestion for structure modification.Thirdly, the modal analysis of the rear axle house was carried out in order to attain the natural frequency and vibration shape of the rear axle housing. It shows that the 1st natural frequency is much higher than road disturbance frequency.Then, with the consideration of the factors which influence fatigue life, such as stress concentration, size, surface processing, the S-N of material were revised. Through the simulation analysis, according to the evaluation method of QC-T 534, the life distribution of the whole axle house and the fatigue lives of the most damaged points were obtained. By comparing the failure position and fatigue lives of the axle house in the bench test, the results of the prediction and the test are consistent.The structure of rear axle house was modified by means of adding fillet to the area, where is most likely to lead to stress concentration, then with the new structure, bend stiffness and static strength were analyzed again, the result shows that the modification is of use to decrease the stress of the axle house and control the phenomenon of stress concentration.