Components-Materials-Contact interactions in braking systems and aircraft compressors
Original Language Title: Interactions multi-échelles Composants-Matériaux-Contact dans les systèmes de freinage et les compresseurs aéronautiques
In turbojet aircraft engines, reducing fuel consumption and specific emissions of CO2 and NOx need to control the clearance between rotor and stator and consequently to master the blade-casing interactions. These interactions are strongly conditioned by the choice of the coating inside the casing.
With regard to braking systems, regulations intend to reduce environmental impacts (noise, particulate emissions) and to increase performance of energy dissipation (high speeds). These specifications need to master the phenomena of friction and the choice of materials in contact.
The project's objective was to develop a methodology to design multi-scale friction materials. This methodology filled in the missing link within the process of understanding and modelling systems (brakes and rotor-stator assemblies for jet engines) in order to increase their energy efficiency and to reduce environmental impacts (noise, air pollution, etc.) while maintaining reliability as part safe.
The main benefits were to achieve:
- A methodology to "design" friction materials for brake applications and casing coatings for turbojet engine.
- A multi-scale modelling of material - contact interface, integrated into the industrial methodology for analysing performance of brake systems and aeronautic engines.
- From a scientific perspective, the major benefit is a "homogenization tribological interpretation" that will be a first in tribology.
Due to high complexity, the approach relied on the one hand on the identification of physical dominating phenomena and, on the other hand, on an experimental-numerical dialogue.
The approach was based on the following key points:
- Definition of "model materials" representative of industrial material formulations reduced and controlled, which will be characterized in terms of heterogeneities and properties.
- Approved friction tests with quantitative characterization of material properties and interface (third body) and their gradients. Innovative ways to rheological characterization will be implemented (rheometers and meso-tribometers).
- Multi-scale multi-physics numerical innovative approach considering the heterogeneity of materials and interface. This will be done through multi-scale numerical and semi-analytical homogenization.
- FTG Faiveley Transport Gennevilliers
- FBF Foundation Brakes France S.A.S
- IJLRDA Institut Jean Le Rond D'Alembert
- INSA DE LYON - LAMCOS Institut National des Sciences Appliquées de lyon - Laboratoire de Mécanique de Contact et des Structures
- KUL Katholieke Universiteit Leuven
- LML Laboratoire de Mécanique de Lille