M. A. Saeedi, R. Kazemi, M. Rafat, A. H. Pasdar,
Volume 2, Issue 2 (4-2012)
Abstract
In this paper, a complete model of an electro hydraulic driven dry clutch along with its
performance evaluation has elucidated. Through precision modeling, a complete nonlinear
physical and full order sketch of clutch has drawn. Ultimate nonlinearities existent in the
system prohibits it from being controlled by conventional linear control algorithms and to
compensate the behavior of the system mainly during gearshift procedure, a nonlinear control
program has been developed and tested. A unique approach to estimating clamp force has been
adopted which makes the system comparable to a real world and full-physical one. Based on
this type of modeling, the control approach is a true and feasible, ready-to-implement program
which is based only on reality. The clutch model has been validated against experiments and
great agreement has been attained since, every fine point has been taken into account and
nothing is out of representation unless it is not crucial to system performance. The nonlinear
control program does the control task very well and administrates the system in the desired
trajectory.
Mr. Seyed Ali Mousavi, Dr. Saeed Mahjoub Moghadas, Dr. Hosein Mansouri,
Volume 16, Issue 1 (3-2026)
Abstract
In the automotive industry, reducing torsional vibrations caused by combustion irregularities and internal inertial forces is essential for improving powertrain quality, NVH (Noise, Vibration, and Harshness), and component durability. This study introduces and analyzes an innovative dual mass flywheel (DMF) with polymer bearings, aimed at enhancing torsional damping and ensuring smoother torque transmission in six-cylinder gasoline engines. The DMF consists of two masses, low-stiffness springs, and polymer bearings, all thoroughly modeled. Both linear and nonlinear dynamic analyses were performed, incorporating factors such as centrifugal force, nonlinear friction, and viscous damping. Component parameters were obtained via modal tests and experimental measurements. To validate the model, cylinder pressure and torque data were collected using sensors and a dynamometer, then compared with simulation results. Results reveal that employing the DMF reduces output torque fluctuations by up to 89.9% and significantly increases torsional vibration damping without a notable weight increase. Compared with a single-mass flywheel of equal inertia, the DMF decreased torque fluctuation amplitude by 46%, 41%, and 38% at 2250, 3000, and 3750 rpm, respectively. Achieving similar damping with a single-mass flywheel would require over an 80% mass increase. The nonlinear model provided a close match to experimental data, with simulation error below 5%. Overall, this integrated approach demonstrates that the dual mass flywheel with polymer bearings improves dynamic engine performance, NVH, and powertrain durability. These findings support the development of lighter, more advanced powertrain systems for next-generation vehicles.
