Oscillations of Plates with Mixed Boundary Conditions at the Edges in Different Media

The frequency spectrum and forms of bending vibrations of rectangular plates in contact with liquid or gas are determined, when two edges from one vertex are hinged, and on the remaining edges there is a movable seal. The plate surfaces are in contact with a medium of different density and pressure. The medium can be compressible during the deformation of the surface and incompressible. The effect of density, average pressure, tension force, and the added mass of the gas medium on the frequency spectrum is determined.