University of Ottawa

Purpose

The aviation industry is committed to decarbonisation. Among the options, hydrogen (H2) holds great promise for long-haul airliners. Within the H2 portfolio, H2 fuel cells may not meet the power-density requirements for longhaul applications in the near future, which leaves H2-fueled gas turbines as the one viable technical pathway. H2 as an aviation fuel is fundamentally different from kerosene-based jet fuels and brings great new potentials: it is stable at the elevated temperatures of engine hot-gas path components (combustor liners and turbine blades). In addition, H2 needs to be stored either as a cryogenic liquid or as a cryocompressed gas. The endothermic process of vaporizing or pre-warming H2 from its storage states can be perfectly matched with demanding cooling requirements of aero-engines. To take full advantage of the new fuel, this collaboration plans to develop a novel engine architecture where H2 is also used as engine coolant that eliminates the extra weight and energy requirements of vaporizers and/or multiple heat exchangers for pre-conditioning the fuel. Meanwhile, the need for diverting compressor discharge air for cooling can be greatly reduced or fully eliminated, resulting in 10-15% engine efficiency improvements over kerosenefueled legacy engines. The end goal of this undertaking is to have a proof-ofconcept combustor demonstrator that pre-heats low-temperature H2, needs little or no additional cooling air, and can combust H2 cleanly and efficiently by taking advantages of new additive manufacturing capabilities in both high-temperature superalloys and ceramics.