10. A Validation Program for Dynamic High-Lift System Aerodynamics

The feasibility of laminar flow control technology for future wing is bound to the development of a leading edge high-lift system that complies with the requirements on smooth surfaces to enable maintaining the laminar boundary layer flow, such as a Krueger flap. The European H2020 project UHURA, running from September 2018 to August 2022, has been focusing on the unsteady flow behavior around such high-lift system. It first time delivered a deeper understanding of critical flow features at this type of high-lift device during its deployment and retraction together with a validated numerical procedure for its simulation. UHURA performed detailed experimental measurements in several wind tunnels to obtain a unique data set for validation purposes of Computational Fluid Dynamics (CFD) software, including detailed flow measurements by Particle Image Velocimetry (PIV) and other optical measurement technologies. Advanced CFD methods promising significant improvements in the design lead time have been applied and validated against this database to obtain efficient and reliable prediction methods for design.