The development of Ultra High Propulsive Efficiency (UHPE) engines is a promising challenge to fulfil the objectives of CleanSky 2 ITD ENGINES program and the potential for significant reduction in fuel burn, emissions and perceived noise to the level defined by “ACARE 2035”. Current engine designs are indeed reaching their limits in terms of efficiency (i.e. conventional bypass ratio (BPR) is about 9-10, future UHBR target is 12-15). This is mainly the reason why innovative architectures like the geared turbofan concept are the promising enablers for UHPE engine success. The development of such Integral Drive System raises different technological challenges at the system and component scales. BrEATHE project, standing for BEAring Technology for High Efficiency, will focus on the planet component, the central module of the transmission system of the high power gearbox, where the bearings are key elements. The specificity of the BrEATHE bearing remains in functional integration: a gear with integrated bearing outer raceway.
BrEATHE project objectives can be divided in these main steps:
1. Design of a bearing to be mounted in a high-power gearbox
2. Low TRL evaluation of high-performance steels.
3. Production of the prototype bearings
4. Testing of the bearings
5. Model correlation based on test results
The step 3 to 5 have not been performed in the framework of the project, although the project has not been completed, the continuation of the research is expected to provide key bearing technologies (material and design) and advanced computational models enabling the development of the innovative power gearbox of the future UHPE engine and other next generation engines to meet the objectives of the Clean Sky 2 programme in terms of environmental benefits and European competitiveness such as the reduction of aircraft CO2 & NOx emissions, the validation of innovative engine technology and employment.
