In this study, the dynamics of the drivetrain of a passenger car equipped with a three-cylinder engine and a five-speed manual transmission were simulated and compared in two configurations: single-mass flywheel (SMF) and dual-mass flywheel (DMF). The influence of the DMF on reducing torsional vibrations and drivetrain oscillations transmitted to the gearbox and the vehicle was subsequently evaluated under various operating conditions. For this purpose, a powertrain model with 44 torsional degrees of freedom was developed in AVL EXCITE™ PowerUnit software, and a wide range of vehicle operating scenarios—including engine start-up, idle, vehicle launch, creep, drive and coast speed sweep, tip-in and back-out, and engine stop—were analyzed. In addition, for the driving speed sweep condition, the simulation results in 4th gear were validated with experimental data.

The results indicated that the DMF significantly reduced the torsional fluctuations transmitted to the gearbox in quasi-steady conditions such as idle, creep, drive and coast speed sweep. In transient conditions, however, the system exhibited more complex behavior. During start-up, stop, and launch, an increase in drivetrain oscillations and vehicle linear acceleration fluctuations was observed. In contrast, in tip-in and back-out maneuvers, the DMF led to a noticeable reduction in input shaft oscillations of the gearbox.

Overall, the use of a DMF generally improves the dynamic behavior of the powertrain; however, under certain transient operating conditions, such as engine start-up, its performance exhibits limitations. In addition, the DMF increases crankshaft angular velocity fluctuations. Combined with the altered distribution of inertia between the crankshaft and the transmission input shaft, this requires further analyses of other components, such as the crankshaft, to ensure optimal DMF performance.