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Self-excitated vibrations are a well-known phenomenon in mechanical systems. They may be caused by internal damping of an elastic rotor or a steady wind flow impacting a structure, and these are just two important examples. Self-excited vibrations are an unfavorable phenomenon in most mechanical systems. Many researchers have dealt with the
problem of suppressing self-excited vibrations and mostly passive means have been
suggested. Recently, a new semi-active approach has been intensively studied. It is based on using a periodic excitation of the system parameters.

In this contribution we discuss the possibility of a full suppression for self-excited vibrations of a mechanical system using a zero-mean
random parametric excitation (random noises). A two-mass system excited by a flow, generated by a
force is considered. Synchronous and random stiffness and damping excitations have been
used for full vibrations suppression in this system. Five sources of zero-mean excitations are considered.
The advantages and deficiencies of this method are compared to the previous approach. The mechanism of suppression by random parametric
excitations, investigated here, is based on the effect of coupling modes by these excitations. The numerical analysis is based on the mean square stability of stochastic dynamical systems.