Symmetry and Self-excitation: Research Activities Related to Rotors in Frictional Contact
Dr. Gottfried Spelsberg-Korspeter
Technische Universität Darmstadt
Date: Wednesday, February 29, 2012
Place: EA 409
Friction is used for many different purposes in engineering. In brakes it is used to slow down a vehicle whereas in piezoelectric motors the frictional contact is needed to drive the rotor. In technical applications with friction, self-excited vibrations can arise that may be wanted or unwanted. Examples for unwanted self-excited vibrations can be found in disk brakes, clutches and paper calenders among others. In other systems a systematic generation of a self-excitation may be desirable for example in the field of energy harvesting. It can be shown that the occurrence of self-excited vibrations is strongly related to symmetries of the structure. This knowledge can be used to suppress vibrations such as in the brake squeal problem or to initiate self-excitation for energy harvesting.