Trailing edge flaps in high-lift configuration are prone to turbulent flow separation on the suction side, which leads to a drop in lift and an enormous increase of drag. Active flow control (AFC) is an appropriate instrument for avoiding flow separating and therefore enhancing aerodynamic performance depending on the desired application. The superior goal of the Smart Fixed Wing Aircraft (SFWA) project is to prepare a large-scale wind tunnel (w/t) test with AFC applications on a trailing edge device in order to close the gap between mid-scale w/t testing and applications on aircraft level.
The main task of this particular project mentioned in the call for proposal (CfP) is focused on developing an actuator system based on pulsed pressurized and / or piezoelectric flow control technique for delaying separation onset on trailing edge (TE) device. Moreover, a sensor system and a signal processing unit have to be developed to detect flow separation in order to close the control loop. Accordingly, the synthesis of a robust controller has to be addressed so that this system works transiently in all possible situations including scenarios with external disturbances. Subsequently this closed loop (CL-) AFC technique has to be investigated in a mid-scale w/t test arrangement at higher Reynolds numbers and including the swept case for more realistic flow field which is requested in the CfP of this particular project.
The experience and data which will be achieved within this project will be the base for large scale w/t tests regarding AFC planned for the future. Technische Universität Berlin was and nowadays is involved successfully in national and European projects, such as SFB, M-Fly or AVERT, dealing with AFC. Hence TUB has a large background in AFC on high lift devices with experiences of more than 10 years and is a very appropriate partner for realizing the goals of SFWA project and meeting the vision 2020.