Wing-in-ground craft longitudinal modeling and simulation based on a moving wavy ground test

Abstract

Compared with the static wavy ground tests and moving flat ground tests, the moving wavy ground test eliminates the effect of the boundary layer and generates more accurate test results of the aerodynamics in the wave environment. This paper introduces a wind tunnel test of a wing-in-ground (WIG) effect craft with moving wavy ground. The wavy ground is made of elastic material and installed on a moving belt to simulate the relative motion of the WIG craft and the wavy water surface. The test focuses on the relationship between aerodynamics and the waves and indicates that longitudinal aerodynamics is affected not only by wave height but also by wave height change rate, while the lateral and directional aerodynamic characteristics are less affected by the ground effect. The longitudinal aerodynamics and flight dynamics model considering the wave height change rate are established based on the test results. The waves adopted in the dynamics model are random waves to simulate the natural wave environment better. An H∞ controller is designed to deal with the more complicated wave disturbance. The simulation results show that the aerodynamics and flight dynamics model can reasonably simulate the flight of the WIG craft in the wave environment, and the H∞ controller can effectively deal with the wave disturbance and generate a smooth flight.