Boundary layer separation on an airfoil at a low Reynolds number

Abstract

Boundary layer separation on the upper surface of a NACA0012 airfoil at low Reynolds number is numerically investigated. The governing equations are discretized with finite volume method. Second-order Adam-Bashforth and central difference schemes are used for time and space discretization. The boundary layer separation is examined through the velocity profiles, the skin friction distribution, and the flow structure. Beyond an angle of attack of 8°, a small separation region is detected near the trailing edge of the airfoil. As the angle of attack increases, the separation region grows up and moves toward the leading edge. The negative effect of separation on the aerodynamic performance can be seen clearly on the lift and drag distribution as function of the angle of attack. As the separation grows up, the rate of the lift coefficient decreases and the drag coefficient exhibits a substantial increase.