Finite Element Analysis About Front-Axle Vehicle Of Steady And Dynamical Performances

The automobile front axle finite element analysis is one of important topics in the automobile design field. With the computer technology development, the finite element simulation becomes more and more important means of the automobile structural design. The paper carries on the numerical simulation towards the front axle to understand comprehensively the automobile front axle's stress, the strain distribution and the vibration frequency under different varieties of conditions, and provides the scientific theoretical base for the designer, thus improves design quality, shortens design cycle and reduces design cost.During the front axle modeling process, according to the front axle structural characteristics and the subsequent mesh divide ease, it guarantees the front axle's structure characteristic as well as convenience following finite element analysis, and carries on the partial simplification to the front axle structure, thus establishes front axle's finite element computation shell model.Based on the front axle structural characteristics and bear loading conditions to make appropriate assumption, simplify the front axle entity model into reasonable mechanical model, and choice five static analysis conditions, namely the front axle static full load, Impact load, Emergency braking, Maximum side force and corner sideslip to make loading analysis, and set the loading analysis results as finite element modal's loaded load, and come within the linear elastic to calculate respectively the front axle's tensile strength and yield strength in these five conditions. Moreover, it uses the first and fourth strength theory to collate respectively front axle's tensile strength and yields strength in a variety of conditions, and with rigidity standard to check its stiffness.Meanwhile, combine the finite element Modal Analysis method to conduct Front axle's Modal Analysis. And through Block Lanczos to extract the front 10 stages natural frequency and mode of vibration of front axle to analyze the coupling conditions among the natural frequency, external stimulation, human resonance frequency and mode of vibration in each stage, to provide the theory reference for the front axle structure system's vibration characteristic analysis, the vibration error diagnosis and forecast and automobile's structural dynamic performance optimization design.The analysis results show that front axle can basically meet performance requirements, but in the state of the front axle design of the emergency braking condition, it may cause the rupture of front axle and coil spring sleeve welded region because of inadequate tensile and yield strength, or result in other serious faults such as fail to change direction. And the front axles will easy to have coupling with stimulation frequency of rough road and it also maybe couple with the body's first and second resonant frequency, and then cause resonance and thus reduce front axle's fatigue endurance and affect normal driving and driving safety. Therefore, we should improve the front axle in order to use in the modified vehicles.The finite element analysis method and process towards this kind of commercial vehicle in the paper can be used to provide a theoretical reference on how to improve the structure of the front axle. In addition, the analysis method and process are also applicable to analyze and design other commercial vehicles or cars.