Investigation Of Supercritical Boundary Layer Separation And Control Scheme

In recent decades, vortex generators used in separation control on wing boundary layer have developed rapidly. Some new conceptions such as sub boundary layer, micro & intelligent vortex generators are coming up. In this paper, the boundary layer characteristics of a supercritical airfoil is researched in wind tunnel. From the start to control boundary layer separation and to improve aerodynamics characteristics of this airfoil, three kinds of trapezoid, delta and airfoil shaped vortex generators are designed based on traditional, sub boundary layer and micro- vortex generators conceptual design. It include as follows:1. Provide the experimental research scheme to measure and diagnose boundary layer of airfoil. The satisfied results demonstrated that this scheme is correct and efficient. It provides the reliable foundation on analysis of boundary layer characteristics and vortex generators' design.2. The aerodynamics characteristics of this airfoil is studied in wind tunnel. This studies provides the direction of the research on boundary layer. The results show that the airfoil has better characteristics of lift-drag and pitching, however the performance of stall is poor.3. The characteristics of boundary layer's transition, shape and separation are researched. The details as follows: (l)airfoil surface is turbulent boundary layer flows; (2)velocity figure changed unsteady near the point of boundary layer separation due to randomicity of turbulent flow; (3)the airfoil have better state of boundary layer separation and poor stall characteristics because of the upper surface of airfoil is flat.4. The influence of Reynolds number to aerodynamics and boundary layer is investigated.5. Three kinds of trapezoid, delta and airfoil shaped vortex generators are designed based on traditional, sub boundary layer and micro- vortex generators conceptual design, to study the influence of the shape, height, aspect ratio, chordwise position, spanwise position and direction angles of vortex generators on boundary layer separation control.