INFLUENCE OF SURFACE FLOW ON AERODYNAMIC LOADS OF A CANTILEVER WING

The properties of the characteristic surface flow modes and their infl uence on the aerodynamic loads of a cantilever wing at low chord Reyno lds numbers were experimentally studied. The chordwise variations of t he separation and reattachment locations as well as the length and cen ter position of the separation bubble in the domain of the chord Reyno lds number/root angle of attack heavily depend on the characteristic s urface how modes. The aerodynamic loads, e.g., the lift, drag, and mom ent coefficients, are profoundly influenced by the characteristic beha viors of suction surface flow. The lift coefficient increases with the increase of root angle of attack In the regimes of laminar separation , separation bubble, and transition. The curve of lift coefficient has a largest slope in the laminar separation regime. The increase rate o f the lift coefficient decreases when the separation bubble is formed. The stall happens in the turbulent separation regime. The drag coeffi cient slightly decreases in the laminar separation regime, remains alm ost a constant in the separation bubble regime, and increases in the t ransition regime.