Effect of high-frequency excitation on natural frequencies of spinning discs

The effect of high-frequency, non-resonant parametric excitation on the low -frequency response of spinning discs is considered. The parametric excitat ion is obtained through a non-constant rotation speed, where the frequency of the pulsating overlay is much higher than the lowest natural frequencies . It is shown analytically and numerically that this excitation has the non -trivial effect of increasing these natural frequencies with increasing pul sation amplitude. (C) 2000 Academic Press.