Film damping often occurs in microsystems in which a thin gas film covers a vibrating structure’s surface or is squeezed between two structures. The film dissipates energy from the moving structures and subsequently imposes a damping effect. Film damping can be an unwanted phenomenon, but it can also be used as a controlling mechanism for the transient operation of a component.

Modeling squeezed and sliding films involves coupling the modified Reynolds
equation with the equations for the structural displacements.

Squeezed-Film Gas Damping in an Accelerometer

A common micromechanical device uses variations in the capacitance when the narrow gas-filled gap between two electrodes is squeezed to measure acceleration.