Control of Forced Vibrations

Abstract

Magnetoelastic forced vibrations of a conducting plate caused by either nonstationary external forces of nonelectromagnetic origin, or with the help of a nonstationary harmonic magnetic field, are examined. The following results are conditioned by the interaction of mechanical and electromagnetic processes in oscillating thin bodies. It is shown that with the help of the chosen external constant magnetic field, the possibility of dangerous resonant vibrations of the conventional type, or violent vibrations, can be eliminated in such cases when, in the absence of magnetic field, the system is out of the resonant area. It is established that the presence of a longitudinal constant magnetic field substantially increases the amplitude of forced vibrations if the frequency of the acting force is greater than the natural frequency of the plate in the absence of a magnetic field. If there is an inverse relationship between the natural frequency and the frequency of the acting mechanical force, then the amplitude of vibrations can be decreased by several hundred times (especially in the case of resonance without a magnetic field) with the help of a magnetic field.