GB2624873A - Hydrogen fuel system for an aircraft - Google Patents

Abstract

A hydrogen fuel system, for an aircraft, has a conduit (fig.2,217) delivering fuel from a storage tank (fig.2,104) to a combustion system (fig.2,207) or hydrogen fuel cell (fig.4,440), and a hydrogen disposal system 226 which bypasses the combustion system or fuel cell, and has a catalyst 238, such as a noble metal or metal oxide, to catalytically combust the hydrogen to generate water. The fuel system may be part of an aircraft propulsion system (fig.2,203) with a gas turbine engine compressor (fig.2,204) delivering bleed air to a mixing chamber 232 of the disposal system, mixing gaseous hydrogen with oxygen, generating a fuel to oxygen ratio outside of flammability range before delivery to the catalyst, the chamber may also have a number of turbulence generating baffles 233 reducing flammability range of the fuel. An ejector 234 may entrain air to the mixing chamber using a hydrogen driving flow. A flame arrestor 236 may be provided upstream of the catalyst and the mixing chamber. A heater 235 and/or cooling system may control the temperature of the fuel or catalyst exhaust gases. A number of disposal systems may collect fuel from the liquid or supercritical hydrogen tank, conduit and/or a pump (fig.2,216) housing.