Active flow control systems were being researched as they might allow to reduce the size, weight, and complexity of high-lift devices. Such active flow control systems, however, require effective, efficient, and reliable flow control actuators. TUB has contributed to developing these actuator technologies in JTI-SFWA projects DT-FA-AFC and FloCoSys. In the work proposed here, the next step was taken to further the TRL level of the devised fluidic actuators by redesigning them with respect to enhanced robustness and putting them to test in the numerous harsh environment situations the AFC system would encounter when implemented in practice.
By combining the input from major industry partners in the field of aviation, such as Airbus and Dassault, the testing capabilities of INCAS, and the experience of TUB in developing and testing actuator, it is hoped to contribute to reaching TRL 6 for flow control actuator technology.
Active flow control by means of pulsed blowing has proven to be effective and efficient to delay or avoid completely flow separation on aerodynamic bodies and therefore allows to increase their operating range. Such active flow control systems, however, require effective, efficient, and reliable flow control actuators. Preceding CfP projects within CS-SFWA (e.g. FloCoSys and DT-FA-AFC) provided the design and validation of a two-stage fluidic actuator, which generates pulsed air jets suitable for flow control applications without incorporating any moving or electrical components. This unique feature of fluidic components allows the design of extremely robust actuators, an overwhelmingly relevant aspect when considering the application of flow control technology in civil aviation. The project robustAFC aimed at furthering the TRL (Technology Readiness Level) of those actuator subsystems.
The approach to reach that aim was twofold: Extensive investigation of the internal flow field of those actuators allowed to increase the in-depth understanding of the switching mechanism inside the device and in consequence enabled the design of flow control actuators with superior performance. Concurrent work focused on the testing of actuator prototype samples in a simulated environment that is equivalent to the environment that the subsystem would encounter when integrated into an aircraft. Those tests were carried out on site at the SFWA consortium member INCAS and the extensively analysed at TUB. Those experiments unveiled weaknesses in the original actuator design and allowed the formulation of recommendations for an improved concept leading to a flow control actuator that offers increased robustness and better aerodynamic performance.
Within the project the feasibility was proven to move the two-stage fluidic actuator up to TRL5.