THE POINT-LOAD SOLUTION USING LINEARIZED VONKARMAN PLATE-THEORY FOR A SPINNING FLEXIBLE DISK NEAR A BASEPLATE

In magnetic and/or optical recording on flexible media, an elastic disk rotates at constant angular velocity in close proximity to a stationary baseplate. Such a configuration is used to stabilize the transverse motion of the flexible disk whose natural frequencies and critical speeds would otherwise be too low for stability of the flexible-disk-to-head interface. The influences of coupling between the inplane displacements and transverse deflections (von Karman plate theorY) and of the air flow between the dish and the baseplate are investigated. Steady-state solutions, for this nonaxisymmetric problem, are obtained by linearizing the partial differential equations about the axisymmetric configuration due to the baseplate alone. These equations are solved using an exponential Fourier series expansion in the circumferential direction and a finite difference approximation radially. The results are the transverse and in-plane deflections of the disk and the air film pressure. Comparisons are made with other models in which von Karman effects have been omitted and in which the airflow has been treated in a simplified manner.