Linear Computational Fluid Dynamic Analysis of Dynamic Ground Effect of a Wing in Sink and Flare Maneuvers

Abstract

A numerical investigation has been conducted to analyze the influence of the dynamic ground effect on the aerodynamic characteristics of a rectangular wing. The numerical model is based on a three-dimensional panel method and the ground effect is analyzed using the method of images. Before simulating the wing approaching the ground, the model developed was tested assuming fixed height and the results were examined by comparison to analytical and numerical results showing a good agreement. Then, the dynamic ground effect was investigated for two flight conditions: constant rate of descent and varying rate of descent. The results obtained by dynamic ground effect and those ones computed using static ground effect were compared evidencing that the static ground effect underpredicts the lift coefficient and overpredicts the induced drag coefficient. In addition, for these flight conditions, the lift coefficient increases when non-dimensional height decreases observing that it is more significant for a constant value of rate of descent, and the induced drag coefficient decreases while non-dimensional height reduces evidencing a significant decrease for a varying rate of descent. Finally, the effect of the flight path angle was evaluated demonstrating that the lift and the induced drag coefficients decrease with more negative flight path.