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 excitation 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 pulsation amplitude.