Unsteady Numerical Simulation of Wings with Flaperon Flying Over Nonplanar Ground Surface

A boundary-element method is developed for the conceptual design of A high-speed transportation system for flying over a nonplanar ground surface. The method is validated by comparing present results with experimental data and other numerical data. Unsteady aerodynamic characteristics of a tandem wing with the flaperon flying over the nonplanar ground surface are investigated using the present method. When a tandem wing with the flaperon flies inside the channel, the lift coefficients of the wings are increased further because the air trapped by the fence of the channel increases the ground effect. On the other hand, the fence of the channel compensates for the lift decrement of the rear wing due to the wake generated by the front wing. Therefore, there is little change between the flat ground and the channel in the longitudinal stability of the wings. Moreover, because the lift increment due to the channel takes place on both sides of the wing with the same rate of increase, there is little difference between the flat ground and the channel in the lateral stability of the wings.