HESTIA (HydrogEn combuSTion In Aero engines) contributes to reach carbon neutrality in the aviation sector by 2050 in line with the EU Green Deal objectives. In fact, HESTIA focuses on the research into new propulsion systems and fuel sources and, considering that the H2 propulsion involves a climate impact reduction of 50-75% when compared to kerosene, it responds to the need to better understand key phenomena of burning H2 in aircraft engines. The overall objective of the HESTIA project is to increase scientific knowledge related to H2/air combustion in aircraft engines and its related influencing parameters. More specifically, the project will improve the understanding of the H2/air combustion through concurrent work streams: elementary lab scale testing, modelling of specific physical phenomena, development of experimental capabilities and improved modelling methodologies for detailed assessment of H2/air characteristics in representative aeronautical conditions, and benchmarking of performance of incremental and breakthrough injection systems concepts to identify the most relevant ones. To achieve these objectives, HESTIA has a duration of 48 months and is composed of 3 scientific Work Packages, focusing on studying the fundamental physical processes involved in turbulent H2/air aeronautical combustors by conducting in parallel theoretical studies, high-fidelity experiments, and high-performance computations (WP1: Mastering key phenomena of H2/air combustion), developing incremental and breakthrough technologies for injection systems especially designed for the use of hydrogen in an aircraft (WP2: Injection systems design), and on consolidating knowledge from the two previous work packages and apply it to more representative engine environments (WP3: Specifications and operability assessments). The outputs produced thanks to HESTIA are TRL3 experimental databases for different flame configurations; advanced numerical tools for the prediction of thermo-acoustics instabilities; validated turbulent combustion models for CFD; validated models for NOx emissions, cooling effects, flame stability; advanced diagnostics methodologies in H2/air flames to evaluate H2 mixing, NOx levels measurements, flow fields, and thermal effectiveness; validated CFD methods and ‘best practice’ methodology for H2 combustion simulation in aero engines combustor configurations; cross-comparison of the different H2 injection concepts regarding some key specifications and selection of concepts that can provide a significant reduction of NOx emission (TRL2/3); a roadmap to mature H2 injection technology to TRL6 by 2028. To deliver these outputs, and so to achieve its objectives, HESTIA can count on a consortium coordinated by Safran and composed of 5 European aero-engine manufacturers and 18 universities and research centres.
