Turboprop engine is the key to contribute to the EU competitiveness growth as well as to tackle the important commitment of sustainable and green transport (SAGE programme). This innovation will be clearly addressed also by the bearings that are directly involved in power efficiency and reliability, highly crucial for the engine development itself. BEATTI project proposes advanced bearings (in term of material and design) with improved dynamic and thermal behaviours and resistance to harsh environment, such as corrosion, particle pollution and poor lubrication condition. To propose the best solution, it is crucial to, firstly, build up failure modes database based on field return functional analysis and testing outputs, and secondly to monitor the bearing usage condition and failure mode with advanced monitoring solution both on engine demonstrator and bearing testing rigs. By knowing real conditions it is possible to propose real solutions. In addition BEATTI will focus on the time to market for the introduction of new material: the ratio “time/resources” of new material introduction will be optimised by focusing on the best TRL level testing. The BEATTI project is thus “the development of advanced bearing solutions, enablers for the next generation of Turboprop engines that will overcome current bearing performances. An innovative approach will be applied coupling a better knowledge of usage conditions & failure modes (using advanced monitoring tools) with specific experimental demonstrations of material and design choices.”

The Ultra High By-pass Ratio (UHBR) engine provides environmental benefits through a high power gearbox decoupling fan and turbine speeds. To implement such engine different technological issues raise: the increase of the i) rotational speed, ii) harsh lubrication conditions and iii) power density. The design of the rolling bearing, crucial component, can affect the gearbox and engine efficiency, performance and reliability. The aim of BrEATHE is to develop, design, model and test a rolling bearing to be mounted in a high power gearbox, including investigation for new high loaded materials, development of models to predicts bearing behavior, producing samples and test them in dedicated test bench. Specific project objectives are: - To define the geometry and perform the design of the bearing. To predict heat generation and transfer in the planet bearing through interactions between dynamic and thermal behaviours. - To demonstrate a -30% in power loss & oil flow and a 15% increase in rolling contact stress capability in comparison to the current baseline solutions and without any detrimental effect on reliability. - To assess the benefits of different process technologies and materials in reaching the efficiency and stress capability required by the gearbox and engine architecture. Including design optimization, comparison of different case hardened steel grade coupled with ceramic rolling elements. - To produce a sufficient number of bearings to sustain the test plan based on a dedicated test bench. To demonstrate their enhanced performances, the BrEATHE new bearing technologies will firstly assessed through modelling and then testes in full-scale testing, with full duty cycle representing the real flight spectrum. The gained theoretical knowledge will enable the transfer and exploitation of projects results to the industrial field by providing analysis tools and new design rules.

The development of Very High Bypass Ratio (VHBR) engines is a promising engine concept to fulfil the major milestones of the Sustainable and Green Engines (SAGE) programme. The significant environmental benefits of this new engine are synonymous with an increased speed and loading capabilities. In terms of engine performance and reliability, the design, sizing and capacities of the rolling element bearings, which are crucial components, can affect the whole engine architecture. The aim of the ARCTIC project is thus: “to develop and demonstrate various rolling bearing technologies that overcome the current design rules of aero-engine bearings and allow developing a VHBR engine”. The main activity is the development of a new corrosion resistant carburized steel grade with the associated surface technologies. Coupled with ceramic rolling elements, this novel material solution will demonstrate a 15% improvement in rolling contact stress capability and 25% increase in rotation speed if compared to the current baseline solutions and without any detrimental effect on reliability. In parallel, powder metallurgical steel grades will be also developed to assess the potential of this breakthrough technology that will act as building blocks for a 30% increase in contact stress capabilities. To demonstrate their enhanced performances, the proposed new bearing technologies will be tested in nominal and in degraded running conditions (from the elementary scale to the full- scale). In addition, across-the-board action will aim to develop a new contact model to fully justify the experimental outputs: the gained theoretical knowledge will enable the transfer and exploitation of projects results to the industrial field by providing analysis tools and new design rules. The ARCTIC consortium offers high-level engineering capabilities, performance test facilities and manufacturing units necessary to develop a European advanced bearing technology for future VHBR engines.

The development of Ultra High Propulsive Efficiency (UHPE) engine is a key factor to fulfil the main milestones of the engine ITD program: high environmental benefits of UHPE will be reached through a power gearbox decoupling fan and turbine speeds. Such innovation raises different technological challenges: the increase of the rotational speed and harsh lubrication conditions due to the centrifugal field. In terms of power gearbox performance and reliability, the design and lubrication of the rolling bearings, crucial components, can affect the gearbox and engine architectures. The scope of PROBATE is “to predict bearing behaviour (through dynamic, lubrication & thermal coupled modelling) and develop various planet rolling bearing technologies, overcoming current design rules of aero-engine bearings enabling the development of a UHPE engine”. Specific objectives are: - To develop a new numerical model able to predict heat generation and transfer in the planet bearing taking into account interactions between dynamics, lubricant and thermal behaviours - To develop an optimized profile ceramic roller, an optimized lubrication solution as well as their integration in the new planet bearing - To demonstrate -30% in power loss & oil flow and -15% of the bearing weight in comparison to the current baseline solution & increasing at the same time the reliability. To demonstrate their enhanced performances, the PROBATE new bearing technologies will firstly assessed through modelling and then tested with elementary and sub-scale testing. The gained knowledge will enable the transfer and exploitation of projects results to the industrial field by providing analysis tools and new design rules. SKF AERO-BV-ENGINE have well-known high-level engineering capabilities in the aerospace filed, performance test facilities and manufacturing units necessary to develop a new advanced bearing technology for future UHPE engine.

Climate-neutral aviation will require the use of alternative fuels such as Green Hydrogen and Sustainable Aviation Fuel (SAF) combined with the power density of an ultra-efficient gas turbine engine for the Short and Medium Range (SMR) aircraft market which corresponds to approximately 50% of the current share of air transport emissions. Rolls-Royce (represented within the HEAVEN project by RR-UK & RR-D) supported by key UK and European academia, industry and research centres are currently developing a new generation of very high bypass ratio geared engine architecture called UltraFan® which was started in 2014. From the beginning this ducted engine architecture has been designed to be scalable and meet the needs both of widebody and SMR markets. To achieve the necessary 20% fuel burn reduction Rolls-Royce proposes to significantly evolve the UltraFan design. The evolved engine architecture design will take the next steps in improving the efficiency of the gas turbine, take advantage of the properties of net zero carbon fuels such as Hydrogen to improve efficiency, combining this with Hybrid electric technology to reduce wasted energy. Numerous innovative enabling technologies already at TRL3 will be incorporated into this new architecture to improve the gas turbine efficiency. Together with work on Hydrogen in CAVENDISH (HRA-01) and Hybrid Electric in HE-ART (HER-01) Clean Aviation projects in conjunction with activities in national and regional programmes, this will be synergistically combined to validate up to TRL6 the highly innovative UltraFan design to support a 2035 EIS. HEAVEN brings together a highly specialised European industrial and academic consortium already strongly involved and familiar with the UltraFan programme. Additionally, the partner easyJet, European airline operator who have the largest fleet of European manufactured SMR aircraft operating in Europe, will bring an in depth knowledge of operational requirements and impact in this market.