Numerical Simulation on Three-Dimensional Air-Cushion and Suction Pad : Discrete Vortex Stick Method

Abstract

The purpose of the present work is to simulate the three-dimensional flow in an air-cushion and suction pad, which acts as repulsive and suction forces to strips, by ejecting a jet to the surface of the strip. A new type of pad, which uses an annular jet, is proposed to generate the strong repulsive force. A simple numerical calculation using the discrete vortex stick method is carried out to study the generation mechanism of the repulsive and suction forces. The numerical results of the development of transient flow in the gap between the pad and the surface of strips is discussed. The results show that the existence of circulatory flow outside the jet plays an important role in generating negative pressure, and circulatory flow is constantly formed in the gap in the case where the length of the pad fringe is large whereas the gap clearance is not so large.