Torsional Vibration Characteristics Analysis Of Vehicle Driveline And Research On Anti-torsional Design

With the development of society and constant innovation of technology industry, not only the automotive industry develops rapidly, but also the automotive performance becomes better. At the same time, people’s demands for car have been from simple walk to a high level. The torsional vibration of vehicle driveline as one of the major sources of the construction vibration and noise in the vehicle, has great influence on the NVH quality of the vehicle. Especially, the torsional vibration of the FR car has become an industry wide concern.In this paper, a FR car driveline is regarded as the main study object by adopting the combination of simulation analysis and experimental research. Torsional design research was performed based on the master of torsional vibration characteristics and influencing rule of automotive powertrain.Firstly, vehicle driveline components are simplified and calculate the lumped mass according to dynamic model principles. Calculate the lumped mass dynamic model system parameters to establish the system dynamic model of six torsion vibration. Indicator diagram of several typical operating conditions of engine were calculated by using engine simulation software, then the simple harmonic analysis is carried on in order to provide equivalent system dynamic models of torsional vibration for the exciting torque.To analyze the torsional vibration characteristics of vehicle driveline. The characteristics of torsional vibration model were obtained through the undamped free vibration calculation. The comparison of the system modal frequency of different gears could help us to master the inherent characteristics of driveline. The torsional amplitude value of each inertia and the additional torque of each shaft were obtained through the forced damped vibration calculation. In the way, to be master of the torsional vibration’s response characteristics of vehicle driveline.Driveline torsional vibration experiments are conducted on the base of emulation analysis. Thus get the excitation characteristics and actual response by data. The calculation results were compared with experimental that would result to verify the accuracy of the torsional vibration equivalent dynamic model. Combined with torsional vibration experimental results to evaluate the torsional vibration conditions of driveline.According to the torsional vibration equivalent system dynamic model, on the base of the comprehensive analysis of the key parameters of the model that influence the driveline torsional vibration to propose the idea of the anti-torsional design from resonant and non-resonant. On the one hand, the anti-torsional design of resonance region was progressed based on the parameters design theory of torsional vibration damper. On the other hand the anti-torsional design of non-resonance region introduced the modal synthesis method.About the characteristic, several anti-torsional design schemes such as the adjustment of sensitive parameters, TVD parameters design, DMF parameters design and flexible coupling parameters match were studied. After verifying the experiments of parts of the schemes, achieved good results for anti-torsional and meanwhile the automotive noise was decreased obviously.Finally summarizes the research of achievements of this text. The comprehensive assessment for each anti-torsional design scheme has guiding significance for controlling the driveline torsional vibration, and provides reference for solving the problem of NVH which caused by the torsional vibration.