Geometrical Installation and Deformation Effects in High-Lift Flows

Abstract

For a three-dimensional half-model high-lift configuration in a wind-tunnel environment, flow separation near maximum lift is influenced by the presence of geometric details. To examine the influence of these details, three computational fluid dynamics based studies are carried out. The objective is to examine the influence of pressure tube bundles, wind-tunnel walls and model mounting, and the effect of model deformation for a high-lift wind-tunnel halfmodel. Viscous flow computations for a high-lift configuration including pressure tubes and wind-tunnel walls (and model mounting) are performed. Experiences gathered with these flow computations are reported and comparisons to wind-tunnel experiments are made. Four methods are deployed in order to study aeroelastic effects, namely, a lifting surface based aeroelastic method and three fully coupled methods. Three structural models of a high-lift wing are developed. Experiences with three fully coupled methods are reported and benefits and shortcomings are identified. It is concluded that geometrical installation and deformation effects for a half-model high-lift wing in a wind-tunnel environment are significant. The mounting of the half-model has the most significant effect on the aerodynamic coefficients. Nomenclature C D = drag coefficient C L = lift coefficient C L;max = lift coefficient for maximum lift point C l = local lift coefficient k = turbulent kinetic energy L = reference length l = turbulent length scale M = Mach number P 0 = static pressure q 1 = dynamic pressure Re L = Reynolds number on reference length L T 0 = static temperature x, y, z = physical coordinates = angle of attack max = angle of attack for maximum lift point " = turbulent dissipation = spanwise station