CA3ViAR – Composite Aeroelastic and Aeroacoustic Validation in Research
CA3ViAR designs and tests a composite low-speed fan representing UHBR engines to experimentally investigate aerodynamic, aeroelastic and aeroacoustic instabilities. IBK leads coordination, test article design and manufacturing.
Project Overview
CA3ViAR (Composite Aeroelastic and Aeroacoustic Validation in Research) was an EU-funded research project under the Clean Sky 2 Joint Undertaking (Horizon 2020). Its goal was to design, manufacture and experimentally validate a low-speed composite fan demonstrator that reproduces the instability mechanisms typical for Ultra High Bypass Ratio (UHBR) propulsion systems used in next-generation civil aircraft.
The project addressed the industrial challenge of developing efficient and lightweight fan systems while maintaining aeroelastic stability and acoustic performance. Increasing the bypass ratio (BPR) improves propulsive efficiency and reduces fuel consumption, yet also narrows the stable operating range and increases the risk of stall and flutter. Furthermore, larger fan diameters introduce complex aerodynamic interactions at the Aerodynamic Interface Plane (AIP), particularly under off-design and crosswind conditions.
To manage these effects, CA3ViAR designed a Low-Transonic Fan (LTF) with a composite rotor intentionally tailored to exhibit representative instabilities within safe limits during testing. The use of Carbon Fibre Reinforced Polymer (CFRP) enabled precise control of stiffness and mass distribution, supporting advanced aeroelastic design. The fan was tested in the Propulsion Test Facility (PTF) at Technische Universität Braunschweig, Germany, where aerodynamic, aeroelastic and aeroacoustic performance was measured over a broad operating envelope, including conditions close to stall and flutter boundaries.
The project combined numerical simulation and experimental validation to improve predictive accuracy in fan design. CFD (RANS/URANS), FEM modal and flutter analysis, and aeroacoustic prediction tools were benchmarked and refined against test data. This integration of computation and experiment supports the next generation of reliable design methodologies for UHBR fans.
Drawing of test section and test rig.
IBK Innovation GmbH & Co. KG coordinated the project and led the mechanical design of the LTF demonstrator, including the detailed structural design, rotor–stator integration, and supervision of manufacturing through specialized subcontractors. IBK also contributed to the aeroelastic analysis and provided interface management between design and test partners.
Technische Universität Braunschweig (TUBS) led aerodynamic design, rig instrumentation, and test execution in the PTF. Leibniz Universität Hannover (LUH) provided aeroelastic and aeroacoustic modeling expertise, conducting both pre- and post-test analyses. DREAM Innovation srl (Italy) supported aerodynamic shaping and CFD post-test correlation.
By the end of 2023, CA3ViAR successfully delivered a validated open test case for composite UHBR fan research. The resulting experimental and numerical dataset enables future research in coupled aeroelastic and aeroacoustic design methods and serves as a benchmark for both academic and industrial applications.
Contributions & Deliverables
- Coordination of the overall CA3ViAR project
- Mechanical and aeroelastic design of the LTF composite fan demonstrator
- Supervision of manufacturing and integration with PTF test rig
- Contribution to numerical–experimental model validation and dataset publication
Composite low-speed fan demonstrator designed for UHBR engine research under the CA3ViAR project.
Partners
IBK Innovation GmbH & Co. KG
Project coordination, aeroelastic design, test article mechanical design and manufacturing supervision
Technische Universität Braunschweig (TUBS)
Requirements management, aerodynamic design, rig instrumentation, wind tunnel testing
Leibniz Universität Hannover (LUH)
Aeroelastic and aeroacoustic modeling, pre- and post-test validation
DREAM Innovation s.r.l.
CFD support and aerodynamic shaping
Methods, Tools & Facilities
Methods
CFD (RANS, URANS), FEM modal and flutter analysis, aeroacoustic simulation, composite structural optimization
Tools
ANSYS, NASTRAN, Python, MATLAB, OpenFOAM
Facilities
Propulsion Test Facility (PTF) at TU Braunschweig (low-speed test rig with cross-wind capability)
Additional Information
Funding
- Funding body: Bundesministerium für Wirtschaft und Klimaschutz (BMWK)
- Program: LuFo VI Grant number: pending publication (CA3ViAR)
- This project is funded by the German Federal Ministry for Economic Affairs and Climate Action under the national aviation research program LuFo VI.
Duration
09/2019 – 12/2023
Phases: design and simulation (2019–2021), manufacturing (2022), experimental testing and validation
(2023).