Nonlinear vibration of rotating thin disks

The response and natural frequencies for the linear and nonlinear vibration s of rotating disks are given analytically through the new plate theory pro posed by Luo in 1999. The results for the nonlinear vibration can reduce to the ones for the linear vibration when the nonlinear effects vanish and fo r the von Karman model when the nonlinear effects are modified. They are ap plicable to disks experiencing large-amplitude displacement or initial flat ness and waviness. The natural frequencies for symmetric and asymmetric res ponses of a 3.5-inch diameter computer memory disk as art example are predi cted through the linear theory the con Karman theory and the new plate theo ry. The hardening of rotating disks occurs when nodal-diameter numbers are small and the softening of rotating disks occurs when nodal-diameter number s become larger. The critical speeds of the softening disks decrease with i ncreasing deflection amplitudes. [S0739-3717(00)02004-3].