Static Behavior of Circular Air Cushion Considering Boyle Charles’ Law and Elastoplasticity of Film

Abstract

Exact equilibrium conditions of circular air cushions are formulated considering Boyle-Charles' law and elastoplasticity of film. The internal pressure of closed type air cushion reacts to cancel the force of external pressure. Displacement and stress due to the external pressure are smaller than those of the constant pressure type. When the positive or negative pressure approximately twice the initial internal pressure affects on the upper film, the upper or lower film lose tension. After one side of the films lose tension, the air cushion holds the pneumatic stiffness of contained air acting on the other side of film.