Numerical simulation to static ground effect of delta wings with different sweep angles

In this paper, the static ground effect of delta wings with different sweep angles is investigated by numerical simulation. The analyses of aerodynamic force and flow field characteristics show that in ground effect, the “block effect” of ground enhances the windward surface pressure; with the sweep angle decreasing, the “block effect” will be further strengthened, and thus the windward surface aerodynamic force increments due to ground effect increase. Besides, the leeward surface aerodynamic force increments due to ground effect also increase with the sweep angle decreasing, but flow physics is not the same for different sweep angles: for medium and high sweep angles, the leeward surface aerodynamic force increments due to ground effect are attributed to the increase of the suction induced by the enhanced leading edge vortex; for low sweep angles, they are attributed to the suction area extension, which results from the movement of the dispersive leading edge vortex.