Active Flow Separation Control on a High-Lift Wing-Body Configuration - Part 1: Baseline Flow and Constant Blowing

This paper describes the influence of grid resolution and turbulence modeling for a 3D transport aircraft in high lift configuration with massive flap separation. The flap is equipped with spanwise slotted active flow control (AFC) devices to allow studies on active separation control. The effects of constant slotted blowing on the high lift performance are highlighted. Oil flow pictures from a mid-scale experiment in the low speed wind tunnel of Airbus in Bremen (B-LSWT) serve as a validation database for the baseline CFD results. RANS calculations are carried out with and without constant blowing boundary conditions. The baseline flow is also investigated with a time-accurate URANS approach. One of the major outcomes of the AFC study is the demonstration of the feasibility to simulate AFC concepts on a 3D configuration. Constant blowing shows the beneficial effect that separation can largely be suppressed because of the energy added to the flow on the suction side of the flap. This study serves as a preceding validation for the subsequent pulsed blowing approach treated in Part 2