Aerodynamic Correction Research for a Small-Aspect-Ratio Flying-Wing Aircraft in Ground Effect

The ground effect of small-aspect-ratio flying-wing aircraft is more pronounced than that of conventional layout aircraft, significantly influencing their takeoff and landing characteristics. This paper conducts static numerical simulation studies on the aerodynamic characteristics of flying wing configurations in ground effect by solving steady Reynolds-Averaged Navier-Stokes (RANS) equations, obtaining static aerodynamic force characteristics and comparing them with wind tunnel test results. The findings reveal that ground effect induces increased lift slope, reduced induced drag, and enhanced zero-lift pitching moment. Aerodynamic characteristics exhibit significant nonlinear variations with decreasing ground heights. Notably, the wind tunnel test floor boundary layer substantially affects near-ground pitching moments and should not be neglected. The variations of lift slope, aerodynamic center, and zero-lift pitching moment with ground heights demonstrate good agreement between simulations and wind tunnel test data. However, experimental measurements fail to capture the distinct nonlinear variation of zero-angle-of-attack lift coefficient with ground heights.