The Vibiration Fatigue Optimization Analysis Of Torsion Beam-Based On The Rigid-Flexible Coupling Model

Car is composed of tens of thousands of parts and components, including suspension. Suspension is an important component in automobile structure, its performance plays a major role in the vehicle ride comfort and safety, especially after the widespread application in the compact family car due to the low cost and practical of the torsion beam suspension. When vehicle is running, direct incentives from the pavement is passed on to the torsion beam suspension causing fatigue damage and affect the service life. At present, many manufacturers use a large number of experiments to evaluate the fatigue life, the cost is big. Some people try to use the theory and numerical analysis methods to analysis, but confined to a single factor, there is no joint experimental results and numerical analysis on the system analysis. Based on a lot of literature research, this article uses the theory of fatigue life analysis, finite element method and experiments to analyze and optimize the torsion beam rear suspension structure. Main work and conclusions are as follows:(1)Based on the theory of fatigue damage, certain models of suspension torsion beams are mechanical analyzed, reveals the influence factors of the fatigue life;(2)Based on finite element theory, the rear suspension torsion beam form configuration and mechanical characteristics are discussed in detail under quasi static analysis, it is concluded that the first order modal is on the low side, close to the road excitation frequency, caused that the structural strength is insufficient;(3)Based on the loading characteristics of the torsion beam suspension, the vehicle coupled model is established, according to the actual collection of strengthening road spectrum, obtained the modal of the torsion beam rear suspension displacement process;(4)Based on the theory of fatigue life analysis, combining with each order modal displacement process and material s-n curve, the fatigue life of the torsion beam suspension is analyzed, and experimental verified;(5)Based on fatigue analysis results, the structure of the torsion beam rear suspension and suspension parameters are optimized, the service life of the optimized torsion beam suspension is improved.