Numerical investigation of the laminar and drag-reduction control by using suction technology on a supercritical airfoil

Numerical simulation of laminar and drag-reduction control was carried out on both full and partial upper region of a supercritical airfoil; furthermore, the effects of different suction coefficients and Reynold numbers on the transitional position and drag were studied by using the computational fluid dynamics code, Fluent. The results show that: (1) transitional position could be effectively delayed with the full suction control on the whole upper surface, and the upper surface could reach full laminar state when the suction coefficient exceeds some value, so the drag could be decreased. (2) When the suction control is only carried out on 15%~65% of the upper surface, at a certain suction coefficient, the efficiency of drag-reduction is nearly the same as full suction control. (3) When other flight conditions are the same, the efficiency of drag-reduction is better at a lower Reynold number.