Research On Parameter Identification Of Nonlinear Hysteresis Model For Circumferential Arc Spring Dual Mass Flywheel

Vibration,noise and other factors generated by the torsional vibration of automobile transmission system would affect the running stability, creature comforts and fuel economy. The new torsional damper of dual mass flywheel was used widely, which would play an important role in reducing torsional vibration, noise and hardness of transmission system and realizing the overload protection for engine, etc. At present, most researchers had focused on the simulation analysis and description of experimental results of the dynamic characteristics and lacked the study of hysteresis nonlinearity model.The circumferential arc spring dual mass flywheel(DMF-CS) was taken as the research object in this paper. The hysteretic characteristics and its models of DMF-CS were studied more deeply. The corresponding hysteresis model of DMF-CS was established; and the model parameters were estimated applying the experimental data. Therefore, it would provide a theoretical basis for the optimization design, production forecast and performance monitoring, etc of DMF-CS.Firstly,the reasons for nonlinear hysteretic characteristic of the typical DMF-CS were studied in the perspective of macroscopic. Mechanics model of arc spring element was established and recursive equation of restoring force and torsional angle of arc spring was derived, using discrete method. Meanwhile, the static and dynamic torsional vibration characteristics of DMF-CS were simulated and analyzed theoretically. The hysteresis model of DMF-CS was established based on elastic restoring torque and hysteretic damping torque of arc spring. The hysteresis characteristics of DMF-CS was related to the speed, according to the analysis of the theoretical derivation.Secondly, the static characteristics testing bench of DMF-CS was set up, and experimental study on the static hysteresis characteristics of DMF-CS was carried out. The static nonlinearity hysteresis model was established based on the bilinear hysteresis model. According to the simulation data and the experimental results, the parameter identification of the model was found. The model was the general formula of static hysteresis model of DMF-CS, which could well describe the static hysteresis characteristics of DMF-CS and agree well with the test results.Thirdly, the dynamic characteristics testing bench of DMF-CS was set up, and experimental study on the dynamic hysteresis characteristics of DMF-CS was carried out. Therefore, the experimental relationship between restore torque and torsion angle of DMF-CS under different rotational speeds were obtained. The dynamic nonlinearity hysteresis model was established based on the polynomial hysteresis model, whose parameters could be expressed as a function of speed. According to the simulation data and the experimental results, the parameter identification of the model was found. The model was the general formula of dynamic hysteresis model of DMF-CS, which could well describe the dynamic hysteresis characteristics of DMF-CS and agree well with the test results. The equivalent stiffness and equivalent damping coefficient of DMF-CS were calculated, using equivalent average method. The simplified equivalent hysteresis model of DMF-CS was obtained, which made the analysis of DMF-CS tend to be simple, with the research value of the engineering practice.