This contribution discusses numerical investigations of active flow separation control for high-lift configurations under atmospheric low-speed wind tunnel conditions. A two dimensional (2D), 2-element airfoil and a three-dimensional (3D), 3-element, wing body setup are the configurations of interest. The slot-actuators are applied on the suction side of the trailing edge flap to prevent the local flow separation. The active flow control (AFC) method of choice is the pulsed blowing. This study explores the resulting effects of the flow control application on the global aerodynamic coefficients and, beyond this, by the analysis of the resulting loads variation by specific actuation parameters. The computational results highlight the ability of pulsed blowing at moderate blowing momentum coefficients to suppress the flow separation on the trailing edge flap and support the global aerodynamic enhancement.