Dynamic Stability of a Plate Supported by Air Pressure

(Influence of chamber volume and slit width on occurrence conditions of self-excited vibration)

Abstract

This paper presents experiments and an analysis on the self-excited vibration of a plate supported by air pressure. The unsteady fluid force acting on the plate is calculated based on the basic equation of two dimensional gap flow between the plate and a chamber surface. The effect of air compressibility in the chamber is taken into consideration in the basic equation. The system's characteristic equation is derived from the plate motion coupled with the unsteady fluid force acting on the plate. The influence of slit width and chamber volume on the unstable condition of the self-excited vibration is clarified comparing the analytical result with experiments. Lastly, the local work done by the unsteady fluid force acting on the plate (bottom surface) is shown, and the influence of slit width on the unsteady fluid force is discussed.