FLOW SEPARATION CONTROL ON MORPHING WING

The unsteady flow around NACA 4415 airfoil is numerically simulated at Re=5×104, α=3°, and continuous deforming technique based on morphing wing is applied to control flow separation through spring analogy method. The effects of various oscillation parameters (position, frequency, and amplitude) on separated flow characteristics and the coefficients of lift and drag are analyzed respectively. The results show that: 1) the closer the oscillation position is to the separated point, the more significantly the flow separation is reduced; 2) the separated flow can be improved effectively when the oscillation frequency is higher than the natural frequency of vortex shedding from the upper surface; 3) The average lift-to-drag ratio is maximized when the amplitude is 0.00512 times of the chord of airfoil.