Frictionally excited thermoelastic instabilities of multi-disc clutches

Abstract

On the basis of Kirchhofs plate theory, a mechanical model is proposed to describe the frictionally excited thermoelastic instabilities of a stack of sliding annular plates. The thermoelastic feedback of the frictional contacts is characterised by thermal curvatures proportional to the contact pressures. As an example, the critical operation states of a multi-disc clutch of an arbitrary odd number of discs are investigated.

Keywords:

• Thermoelastic instability (TEI)
• frictional contact
• multiple disc clutch
• eigen-value problem
• eigenmode
• critical speed
• plate theory

Additional information

Notes on contributors

C Krempaszky

Born in Ingolstadt, Germany, Dr.-Ing. Christian Krempaszky studied mechanical engineering at the Technische Universität München, Germany. He graduated in 1997 to Dipl.-Ing. at the Faculty of Mechanical Engineering. After four years working as a research assistant at the chair of Material Science and Mechanics of Materials, TU München, he graduated to Dr.-Ing. in 2002. The Faculty of Mechanical Engineering awarded the “Rudolph-Schmidt-Burkhardt-Gedächnis-Preis” to him for the year’s best doctoral thesis.

Since 2002, Christian was an assistant professor at the Chair of Material Science and Mechanics of Materials. Since 2006, he has been the head of the Christian-Doppler Laboratory of Material Mechanics of High Performance Alloys at the Chair of Material Science and Mechanics of Materials at the TU München, Germany. This research group deals with the characterisation of the material and component behaviour in dependence of the production parameters with special emphasis on experimental investigations of the mechanical properties, microstructure evolution and residual stress development. Special attention is paid to the high performance materials as used in thin sheet application, forging applications, and materials applied as tools in forming processes.

Up to now, Christian is the author/co-author of more than 40 publications and more than 50 scientific presentations.

E Werner

Born in Austria, Ewald A Werner graduated from the University of Leoben (Montanuniversität) in 1980, majoring in materials science and metal physics, and earned his doctorate degree in 1984. After two years as a post-doc at the Swiss Federal Institute of Technology (ETH), Zürich, Switzerland, he worked for the Austrian Academy of Sciences in the field of solid state physics.

In 1997, Ewald accepted the offer to join the faculty of the department of mechanical engineering at the Technische Universität München, Germany, as a full professor for Materials Science and Mechanics of Materials. Current research activities include the development, processing and testing of new materials, such as low alloyed TRIP, interstitial free, bake hardening, ferritic-martensitic, ferritic-bainitic and ferritic-austenitic duplex steels, nickel-base and titanium alloys.

Ewald is the author of three text books on engineering mechanics and materials science, authored/co-authored approximately 200 scientific papers, and has given invited lectures in many European countries, in the US, China and Japan. He has been recipient/co-recipient of 10 national and international scientific awards. Since 1999, he has served as co-editor of the scientific journal Materials Science and Engineering A.