The Structural Analysis And Fatigue Life Prediction Of Some Passenger Cars’ Rear Axle Based On Finite Element Method

Car rear axle is an important part of the automobile, it withstands the frame and theroad passing the various forces and moments, so that the rear axle must have sufficientstrength, stiffness and fatigue life. At present, the rear axle Research based on the strengthand stiffness, and fatigue strength than less. Torsion beam rear axle studied in this paperare the fatigue test bench and vehicle testing stage fatigue cracking is typical of fatiguefailure.In this paper, large-scale three-dimensional modeling software UG NX create a three-dimensional geometric model of a passenger car rear axle, and pre-treatment, the use ofshell elements mesh, and the establishment of appropriate MPC unit to facilitateconnections and constraints and loads applied, eventually get the whole rear axle shellfinite element model.The use of finite element analysis software NX Nastran simulation bench test thelimit position of the rear axle housing fatigue durability finite element analysis is appliedto the forced displacement of the rear axle stress contours and displacement contours onthe rear axle typical operating conditions the force analysis, checking the rear axle of thestatic strength and stiffness.Based on the finite element analysis results, the use of professional fatigue analysissoftware Nsoft of the fatigue life prediction of the rear axle, the result that rear axle fatiguedamage distribution histogram and fatigue life contours has been got.Finite element structural analysis of the rear axle of the stress-strain test test resultswere compared to verify the rationality and accuracy of the results of the rear axle finiteelement structural analysis method; also the fatigue life prediction results of the analysisand the rear axle bench. The durability test results were compared, the results show thatthe analysis of the of results frequency and with the experimental results on frequency andmagnitude considerable, but also reflects the accuracy of the analysis results in a certaindegree.Finally, structural analysis and fatigue analysis of the rear axle, the rear axle of theimprovement program, the improved model of the finite element structural analysis andfatigue life prediction analysis, to verify that the improved method is reasonable andeffective sex. Improved rear axle by the user initially, fully able to meet the general needsof the user.