Rotating structures subject to frictional contact are susceptible to self-excited vibrations that are responsible for noise problems. In previous work the underlying mechanism has been explained through mathematical–mechanical models. From practical experience it is known that breaking the symmetry of a rotor can have a stabilizing effect. The present paper is devoted to a mathematical justification of this phenomenon. At the same time a method for a quantitative investigation of the influence of asymmetries on the stability behavior is outlined. As an example a rotating annular Kirchhoff plate in contact with friction pads is studied serving as a minimal model for brake squeal.

A possible application of the results is the support of the design process for squeal free brake rotors where currently only experimental methods yield information about the tendency of an asymmetric brake rotor to squeal.