Research On Torsional Vibration Of The Driveline Of A Passenger Car

Torsional vibrations of vehicle driveline are one of the major factors of the construction vibration and noise in the vehicle, influencing the NVH quality of the vehicle. With continuous increase of the power and velocity of the vehicle, lighter structural quality of the vehicle, higher comfortable ride and safety are required, the torsional vibration of the driveline of the vehicle becomes more and more crucial. Therefore, the study of effect of the torsional vibration on the driveline of vehicle is of practical significance.In this paper, torsional vibration of the driveline is researched based on a passenger car. The basic principle of the torsional vibration is introduced and the lumped mass model method is chosen for the research of the torsional vibration. The components of the driveline are transformed equivalently. The lumped mass-elasticity-damp discrete torsional vibration dynamic model with the 10 DOF is established on the basis of the structure parameters of the components.The force coming from the interferential period torque of the engine is analyzed. The second harmonic order of the interferential period torque is the key factor that influences the torsional vibration of the driveline. This result is proved by the analysis and torsional vibration experiment.Eigen-characteristics of the torsional vibration of the discrete dynamic model is calculated and analyzed by matrix method. The forced torsional vibration of this model is simulated by MATLAB/SIMULINK program and the time domain responses and the frequency domain responses of the torsional vibration of the driveline is analyzed. By comparison of the simulation and the experiment, the third model of the torsional vibration of the driveline is the major vibration under the force of the second harmonic of the engine.The computational results about key factors influencing the torsional vibration of the driveline are provided. The pattern and degree of effectiveness are further discussed. Comprehensive performance and eigen-characteristics of torsional vibrations of the driveline are evaluated as a reference for the further research.