UHURA
Research on unsteady aerodynamics and dynamic loads of Krueger flap deployment and retraction, with IBK contributing coupling tools, FSI analysis and data management.
Project Overview
The UHURA project investigates the complex aeroelastic and aerodynamic phenomena associated with the deployment and retraction of Krueger flaps in modern high-lift systems. These devices, crucial for take-off and landing performance, are subject to strong unsteady aerodynamic effects and dynamic loads during motion, which are insufficiently understood and thus require comprehensive research.
The challenge arises from the Krueger flap’s thin structural configuration and intricate motion kinematics, leading to coupled fluid-structure interaction (FSI) phenomena. The project’s aim is to enhance the predictability and reliability of these interactions through advanced simulation and experimental validation.
UHURA’s objectives are threefold.
First, to validate numerical simulation methods capable of accurately predicting unsteady aerodynamic behavior and dynamic loads during Krueger movement.
Second, to experimentally characterize the aerodynamic properties of slotted Krueger devices using wind tunnel testing and numerical approaches.
Third, to assess design implications on handling qualities, certification aspects, and potential structural weight reduction.
The project is structured in three major phases. The initial phase covers aerodynamic design and the definition of representative Krueger configurations. In the second phase, unsteady CFD simulation capabilities are advanced, and a detailed wind tunnel model is designed, manufactured, and tested. The final phase focuses on validation of simulation results and comprehensive assessment at aircraft level.
IBK Innovation contributes across all phases of UHURA. The company develops a coupling tool for high-fidelity FSI simulations in cooperation with CIRA, performs FEM analyses for the wind tunnel model, and evaluates the coupled aerodynamic–structural response. Moreover, IBK provides load envelope estimations and weight optimization studies at aircraft level, complemented by database management of all project activities.
By combining simulation and experimentation, UHURA delivers validated predictive methods for unsteady Krueger behavior, supporting safer, lighter, and more efficient high-lift system designs for future aircraft generations.
Contributions & Deliverables
- Development of an FSI coupling tool for Krueger deployment simulation (Phase 1–2)
- FEM analysis and structural model validation for wind tunnel testing (Phase 2)
- FSI assessment and load envelope quantification at aircraft level (Phase 3)
- Database management and data exchange infrastructure for project partners (ongoing)
Partners
IBK Innovation GmbH & Co. KG
CIRA
Project coordination, aerodynamic design, CFD development
DLR
Project coordination, aerodynamic design, CFD development
Methods, Tools & Facilities
Methods
CFD (URANS/EULER), FEM structural dynamics
Tools
In-house FSI coupling framework (IBK–CIRA)
Facilities
Wind tunnel testing at DNW facilities
Additional Information
Funding
- Grant number: 769088 – Horizon 2020
- “This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 769088.”
Duration
September 2018 to August 2021