A simple model for the aero--hydrodynamics of ekranoplans

The problem of a wing-shaped body moving close to the air-water interface is addressed in term of an inviscid-rotational model in which the aerodynamic problem is coupled to the water flow by means of suitable interface conditions. A numerical procedure to solve the nonlinear unsteady problem is described. Numerical examples are given for the linearized cases. In particular the steady flow generated by a flat plate at incidence in forward motion over calm water is studied at first. The linearized wave-wing interaction is then analized in the frequency domain.