Analysis and Evaluation of Some Heavy Truck Drive Axle Housing’s Static and Dynamic Characteristics
|Keywords||static analysis structure optimization modal analysis transient response analysis fatigue life analysis|
The automobile drive axle housing is the important carrying and passing component.As a very widely applicable product, banjo axle housing not only supports the weights of the vehicle, but also withstands the opposite force of traction, braking force, lateral force and vertical force as well as the counter-torque act on the wheels and transfer to the frame and body through suspension fork. Moreover, as a result of the long standing alternating load, the axle housing could get fatigue breakdown which occurs suddenly when the truck runs on the road. So, the drive axle housing must have enough intensity, rigidity and good dynamic performance, the reasonable drive axle housing design can also improve ride comfort of the vehicle.The paper is based on the FEM static, dynamic analysis and the structure optimization theory, complete the whole process of the 3D model construction and the FEA by using UG, PATRAN and FATIGUE. The simplified three-dimensional model and finite element model are constructed firstly in the paper. Then the stress distribution and deformation in four typical loading cases are evaluated in the static analysis, in which the drive axle housing bears the maximum vertical force, the maximum traction force, the maximum braking force and the maximum lateral force.; Optimize the axle housing according to the analysis results; The first twelve natural frequencies and modes under the free constraint are obtained in the modal analysis. Solve dynamic load caused by the hypothetic periodic pavement roughness, apply the dynamic load to the model and get the transient response characteristics and fatigue life of the axle housing in the transient response and fatigue life analysis.The analysis results show that the maximum stress of the axle housing is less than the allowable stress value. So the axle housing meets the strength requirement. The maximum deformation per meter of the wheel-center-distance is less than 1.5mm/m, which meets the stiffness requirements in national standards. The optimization indicates that the weight of the axle housing is reduced remarkably and the maximum stress in housing approaches its breaking-point which improves the utilization of the material, and the stress distributes reasonably. The minimum natural frequency calculated by FEM is far bigger than the frequency from road excitation. The resonance of the axle housing won’t happen when this truck is traveling on road. By transient response analysis, we can clearly see the response characteristics of the drive axle housing parts by the action of the dynamic loads. The fatigue life of the axle housing is far bigger than the designated value, and the axle housing doesn’t get fatigue rupture.