Dual mass flywheels in truck powertrains, Modelling, simulations and validation
Licentiate thesis, 2018

The heavy-duty vehicle manufacturers face large challenges when it comes to reducing CO2 emissions from vehicles. The on-going development of more efficient combustion engines leads to an increase in torsional vibrations. In the future, the conventional flywheel and clutch will probably not be enough to protect the gearbox and rear driveline from engine induced vibrations. More advanced technology will be needed.

Dual mass flywheels (DMFs) have been used in smaller vehicles for many years and have shown to reduce the torsional vibrations transmitted to the gearbox. The use in heavy-duty commercial applications is to date very limited.

The work presented in this thesis focuses on DMFs for heavy-duty applications. It comprises modelling, measurements, correlation, development of numerical algorithms and complete powertrain simulations.

Two different DMF simulation models are used. The first one is a piecewise linear model, without the internal DMF parts explicitly modelled. It is used together with the harmonic balance method to evaluate resonances. The simulated results show that with piecewise linear DMF design, sub-harmonic resonance excitation can occur in operating speed range.

The second model includes the DMF internal parts. A simulation method where the dynamics problem is reformulated as a linear complementary problem (LCP) is proposed. The model is correlated based on test rig measurements on a DMF for heavy-duty applications. It is shown that the general DMF behaviour, as observed in the measurements, can be reproduced in the simulations for the speed and torque ranges studied.

The torsional vibrations in a heavy-duty truck powertrain with a single mass flywheel model and with the second DMF model are evaluated with simulations. The effects on resonance modes and frequencies when changing different powertrain parameters are presented. The simulations show that the vibration amplitudes are generally lower with a DMF. Resonance excitation can occur in operating speed range with the DMF and the DMF and clutch properties need to be adapted to the powertrain in order to obtain good vibration isolation in the complete operating speed and torque range.

DMF

simulations

heavy-duty truck

resonances

driveline

dual mass flywheel

powertrain

torsional vibrations

friction

Delta, Hörsalsvägen 7A
Opponent: Dr. Jan Andersson, Volvo Car Corporation, Göteborg, Sweden

Author

Lina Wramner

Chalmers, Mechanics and Maritime Sciences, Dynamics

Vibration dynamics in non-linear dual mass flywheels for heavy-duty trucks

Proceedings of ISMA2018 International Conference on Noise and Vibration Engineering,; (2018)p. 1935-1947

Paper in proceedings

Lina Wramner, Numerical algorithms for simulation of one-dimensional mechanical systems with clearance-type non-linearities

Lina Wramner, Torsional vibrations in heavy-duty truck powertrains with dual mass flywheels

Reduced vibration transmissions - reduced energy consumption and environmental impacts together with an increased competitiveness

Swedish Energy Agency, 2016-04-01 -- 2020-03-31.

Driving Forces

Sustainable development

Areas of Advance

Transport

Subject Categories

Applied Mechanics

Thesis for the degree of Licentiate – Department of Mechanics and Maritime Sciences: 2018:24

Publisher

Chalmers University of Technology

Delta, Hörsalsvägen 7A

Opponent: Dr. Jan Andersson, Volvo Car Corporation, Göteborg, Sweden

More information

Latest update

11/26/2018