Research on the transverse stability of an air cushion vehicle hovering over the rigid ground

The transverse stability of air cushion vehicles (ACVs) hovering over the rigid ground has always been the challenging problem involving cushion aerodynamics and flexible skirt structure dynamics. The transverse stability is investigated numerically and experimentally based on a particular ACV model. The physical process and mechanism are analysed and a numerical method for evaluating the transverse stability is presented. A cushion-skirt communication platform is built for interchanging the force, hull displacement, and skirt configuration between cushion aerodynamics and flexible skirt structure dynamics. The transverse stability is calculated numerically and the stability model experiments are conducted based on a scale craft model, demonstrating that the numerical result is valid well against the model experimental result. The influences of the bag-to-cushion pressure ratio, the length and effusion height of the longitudinal stability skirt on the transverse stability are discussed systematically by the numerical approaches, giving insight to the design of ACVs.