Prof. Dr.-Ing. Hartmut Hetzler

  • Universität Kassel
    Fachbereich Maschinenbau
    Institut für Mechanik
    FG Technische Dynamik

    Mönchebergstraße 7
    34125 Kassel
    t  0561/804 2868
    f  0561/804 2721
    e hetzler@uni-kassel.de





Mechanical Systems with Tribological Contacts 

  • Dynamics of Coupled Multi-field Problems in the context of System Dynamics 
  • Journal Bearings, Porous Journal Bearings, Sealings
  • EHD - Contacts subject to dynamical loading
  • dry friction



Friction Induced Vibrations 
  • Brake Squeal 
  • Stick-Slip-Oscillations
  • Influence of tribological Parameters


Stability and Bifurcation 
  • moving continuar (turbo chargers, vehicle brakes , clutches)
  • nonlinear friction oscillators (bifurcations, stability)  
  • bifurcations in non-smooth systems 
  • bifurcations of equilibrium sets

Shared KIT Industrial Fellowship "Nichtlineare Strukturdynamik"







Zur Stabilität von Systemen bewegter Kontinua mit Reibkontakten am Beispiel des Bremsenquietschens
Dissertation, Universität Karlsruhe (TH), 01/2008, http://digbib.ubka.uni-karlsruhe.de/volltexte/1000007815


Articles (refereed journals)

H. Hetzler: Bifurcations in Autonomous Mechanical Systems under the Influence of Joint Damping, Journal of Sound & Vibration, 2014

D Maier, C Hager, H Hetzler, N Fillot, P Vergne, D Dureisseix, W Seemann: A nonlinear model order reduction approach to the elastohydrodynamic problem, Tribology International, 2014

H. Hetzler: On the Effect of Non-Smooth Coulomb Damping on Flutter-type Self-Excitation in a Non-Gyroscopic Circulatory 2-DoF-System, Nonlinear Dynamics, 2013

B. Wiegert, H. Hetzler, W. Seemann, An Analytical Expression of the Normal Force of Hydrodynamic Line Contacts under Transient Conditions, Tribology International, 2013

B. Wiegert, H. Hetzler, W. Seemann: A Simplified Elastohydrodynamic Contact Model Capturing the
Nonlinear Vibration Behaviour
, Tribology International, 2012

H. Hetzler: On the effect of nonsmooth Coulomb friction on Hopf bifurcations in a 1-DoF oscillator with self-excitation due to negative damping
Nonlinear Dynamics, 2012

H. Hetzler, K. Willner: On the influence of contact tribology on brake squeal,
Tribology International, 2011

S.W. van Buuren, H. Hetzler, M. Hinterkausen, W. Seemann:
Novel approach to solve the dynamical porous journal bearing problem,
Tribology International, 2011

H. Hetzler: Bifurcation Analysis for Brake Squeal,
Proceedings of ASME ESDA 2010, Istanbul

H. Hetzler: Resonance and stability of stationary solutions in linear systems of rotating machinery with periodic parameter variations and external excitation,
Proceedings of ISROMAC 13, 2010, Honolulu

H. Hetzler: On self-excited vibrations due to sliding friction in systems of deformable bodies – general formulation and influence of contact properties,
Proceedings of the 7th EUROMECH Solid Mechanics Conference, Lisbon, 2009; Paper (
pdf), Slides (pdf)

H. Hetzler: On self-excited vibrations due to sliding friction in systems of deformable bodies – general formulation and influence of contact properties
Proceedings of the 7th International Symposium of Vibrations of Continuous Systems (ISVCS 7), Zakopane/Poland, 2009; Paper (
http://www.isvcs.org/ISVCS7-Proceedings.pdf), Slides (pdf)

H. Hetzler: On Moving Continua with Contacts and Sliding Friction: Modeling, General Properties and Examples
International Journal of Solids and Structures, DOI: 10.1016/j.ijsolstr.2009.01.037

A. Boyaci, H. Hetzler, W. Seemann, C. Proppe, J. Wauer: Analytical bifurcation analysis of a rotor supported by floating ring bearings
Journal of Nonlinear Dynamics, DOI: 10.1007/s11071-008-9403-x

H. Hetzler, W. Seemann: Friction Induced Vibrations: Oscillatory Instability with Dissipative and Gyroscopic Influences
VDI-Berichte 2022, S. 179 - 194, VDI Verlag, 2007; Paper(
pdf), Slides (pdf)

H. Hetzler, W. Seemann: Friction Induced Brake Vibrations at Low Speeds: Experiments, State-Space Reconstruction and Implications on Modelling
Proceedings of ASME IMECE 2006, Chicago, USA (IMECE2006-14034), Slides (

H. Hetzler, D. Schwarzer, W. Seemann: Steady-state stability and bifurcations of friction oscillators due to velocity dependent friction
Proceedings of the Institution of Mechanical Engineering - Part K: Journal of Multi-body Dynamics

H. Hetzler, D. Schwarzer, W. Seemann: Analytical investigation of steady-state stability and Hopf-bifurcations occuring in sliding friction oscillators with application to low-frequency disc brake noise
Communications in Nonlinear Sciences and Numerical Simulation (CNSNS), Volume 12, Issue 1, 2007, Elsevier

H. Hetzler, W. Seemann, D. Schwarzer: Analytical investigation of Hopf Bifurcations occuring in a 1DOF sliding-friction oscillator with application to disc-brake vibrations
Proceedings of ASME IDETC 2005, Long Beach, USA (DETC2005-84312)

W.V. Wedig, H. Hetzler:  Non-smooth stochastic systems in vertical dynamics of cars 
Journal of Applied Mathematics, ARC-2004-Special issue 6



H. Hetzler:
Stability and Bifurcation of Equilibria in the Presence of Non-Smooth Damping due to Coulomb Friction,
Proc. of 11th Intl. Conf. on Vibration Problems (ICOVP), Lisbon, 2013

D. Maier, C. Hager, H. Hetzler, N. Fillot, Ph. Vergne, D. Dureisseix, W. Seemann:
Model order reduction on stationary and dynamical isothermal Newtonian EHD contacts,
Proc. of Leeds-Lyon-Symposium on Tribology, Lyon, 2013 

D. Savio, N. Fillot, Ph. Vergne, H. Hetzler, W. Seemann, R. Pasaribu, G.E. Morales-Espejel, et.al.:
Multi-scale modeling of lubricated contacts: a study on the velocity boundary condition at the wall-fluid Interface,
Proc. of 5th World Tribology Congress, Turin, 2013

H. Hetzler:
Friction induced vibrations under the influence of Joint-damping
Proc. of EUROBRAKE 2013, 2013, Dresden

K. Bach, H. Hetzler, W. Seemann:
Dynamic stability of a steady flow in a planar channel
In Proc. of the 10th International Conference on Vibration Problems (ICOVP), Springer Proceedings in Physics, Vol. 139, 2011

H. Vogt, H. Hetzler, W. Seemann
Analytical Investigations on Vertical Dynamics and Tire Forces of Road Vehicles with Nonlinear Suspensions,
Proc. of EUROMECH Nonlinear Oscillations Conference (ENOC) 2011, Rome

H. Hetzler
On the Approximtion of Limit-Cycles in N-DoF Systems near Hopf-Bifurcations
Proc. of EUROMECH Nonlinear Oscillations Conference (ENOC) 2011, Rome

H. Vogt, H. Hetzler, W. Seemann:
On the influence of design parameters and nonlinearities in vehicle suspensions on road deformation
In Proc. in Applied Mathematics and Mechanics (PAMM), 11, 2011

B. Wiegert, H. Hetzler and W.Seemann:
A comparison between elastohydrodynamic and dry hertzian line contacts with regard to their nonlinear vibration behaviour
In Proc. in Applied Mathematics and Mechanics (PAMM), 11, 2011

K. Bach, H. Hetzler, W. Seemann:
On stability and self-excited vibrations in fluid-structure-interaction
In Proc. in Applied Mathematics and Mechanics (PAMM), 11, 2011

C. Körner; H. Hetzler; W. Seemann:
Nonlinear vibrational behaviour of an elasto-pneumatic training tool,
Proceedings of 10th International Conference on Vibrational Problems (ICOVP), Prag, Czech Republic, September 2011.

K. Bach, H. Hetzler, W. Seemann: Stability of a steady flow guided by flexible walls,
Proceedings in Applied Mathematics and Mechanics (PAMM) 9(1), 2010

F. Bauer, H. Hetzler, A. Pagel, W. Seemann: Do Non-linearities Enhance Stability of Bipedal Locomotion?,
Proceedings of SIMPAR 2010, Darmstadt

H. Hetzler: A Perturbation Approach to Bifurcation Analysis and Limit-Cycle Amplitudes for Brake Squeal Problems,
Proceedings of 8th Intl. Conference on Numerical Analysis and Applied Mathematics (ICNAAM) 2010, Rhodes / Greece

H. Hetzler
On the influence of contact mechanics on friction induced flutter instability,
Proceedings in Applied Mathematics and Mechanics (PAMM) 9(1), 2010

D. Schwarzer, H. Hetzler, W. Seemann: Bifurcation Behavior of a 1 DOF Sliding Friction Oscillator
Proceedings in Applied Mathematics and Mechanics (PAMM), Vol.6, Issue 1, Seiten 331-332, 2006, Wiley InterScience

W. Seemann, H. Hetzler: Disc brake vibration at very low driving velocities
Proceedings on Advanced Problems in Mechanics (APM) Conference 2004, St. Petersburg


please refer to the german version of the homepage !