Published online by Cambridge University Press: 03 February 2016
The main objective of the paper is to evaluate the potential of reducing theenvironmental impact of civil subsonic aviation by using hydrogen fuel. Thepaper is divided into three parts of which this is Part II. In Part I thebackground, prospects and challenges of introducing an alternative fuel inaviation were outlined. In this paper, Part II, the aero engine design whenusing hydrogen is covered. The subjects of optimum cruising altitude and airportimplications of introducing liquid hydrogen-fuelled aircraft are raised in PartIII.
The study shows that burning hydrogen in an aero gas turbine seems to be feasiblefrom a technical point of view. If the priority is to lower the mission fuelconsumption, the results indicate that an engine employing increased combustoroutlet temperature, overall pressure ratio and by-pass ratio, seems to be themost attractive choice. The mission NOx emissions, on the other hand,seem to be reduced by using engines with a weak core and lowered by-passratio.